Blackout: Inside Germany’s far-left war on infrastructure

An investigation reveals the scale of sabotage targeting energy and transport networks.

By ALEXANDER DINGER, LENNART PFAHLER
and PHILIPP WOLDIN
in Berlin

^{Illustration by Natália Delgado/ POLITICO}

It was 6 a.m. when Andreas Thomsen realized something was wrong. The lights in his Berlin home refused to turn on. The appliances did not hum. The electric shutters stayed stubbornly shut. The only sound in the house was the steady pumping of his breathing machine.

Thomsen reached for his smartphone. Nothing. No warning. No breaking news alert. He’s 68 years old and suffers from amyotrophic lateral sclerosis (ALS). He cannot survive without his ventilator. It was now running on battery power. He had six hours left.

Only around 8 a.m. did Thomsen learn what had happened: an attack on the city’s electricity supply. Hundreds of thousands of Berliners in the city’s southwest had been left without power. He alerted his caregivers and called the fire department.

What happened to Thomsen that morning in January 2026 was not an accident. The blackout that hit southwest Berlin was part of a series of attacks that have exposed how vulnerable Germany’s infrastructure has become — and how ill-prepared the state is to stop them.

For months, authorities have focused their attention on the threat of Russian sabotage. But a monthslong investigation by WELT — which, like POLITICO, is part of the Axel Springer Global Reporters Network — suggests the more significant threat is domestic. Behind many of these attacks is a small, decentralized network motivated by far-left extremism. Opportunistic and difficult to track, this homegrown network is increasingly willing to target critical systems, with potentially deadly results.

For Thomsen, the blackout meant he was in danger of suffocating. By 10 a.m., his ventilator showed only two hours of battery life remaining. One of his caregivers kept dialing the emergency services. When the fire department finally arrived, it faced a new problem. The heavy rolling gate outside his house wouldn’t open without electricity.  

Shortly before 11 a.m., with just over an hour left, a second ambulance arrived. The lead emergency physician made a decision. The building’s elevator was dead, and Thomsen could not be carried down the narrow staircase with his stationary ventilator.

The ambulance was equipped with a mobile ventilator. But to get there, he would have to be disconnected.

“It felt like drowning,” Thomsen recalled. Only once he was inside the ambulance was he able to breathe again. “That’s when I realized how close it had been.”

Later, an outfit calling itself the Volcano Group claimed responsibility for the attack. In a statement published online, it dismissed sympathy for the residents of the affluent neighborhoods affected. There was no mention of the people whose lives it put at risk that morning. Germany’s federal prosecutor is now investigating the incident, and has informed Thomsen that he will be interviewed about his experience.

For investigators, the Volcano Group’s claim was both familiar and frustrating. The name had appeared repeatedly over the past decade in connection with acts of sabotage against rail networks, power lines and the construction site of Tesla’s first European gigafactory. The German Interior Ministry attributes at least 13 attacks to the group, but investigators believe that it is less an organization than a label — one adopted by different perpetrators.

Authorities suspect the January blackout is linked to a similar attack in September 2025, when unknown perpetrators set fire to two power pylons in southeast Berlin’s Johannisthal municipality. Their target was the electricity supply to the Adlershof technology park, one of the largest of its kind in Europe. Tens of thousands of households lost power, some for days. The damage ran into the tens of millions. Shortly afterward, a claim of responsibility appeared online, signed simply: “Some anarchists.”

At the time, the case seemed exceptional. In hindsight, investigators now see it differently. Security authorities believe the perpetrators of the Johannisthal arson attack and those behind the January blackout in southwest Berlin come from the same milieu: a loose, clandestine network of left-wing activists that has proven difficult for authorities to keep track of, let alone stop.

‘Disconnect’

Through conversations with police officers, prosecutors, domestic intelligence officials and security policymakers, granted anonymity to speak frankly, WELT reconstructed many of the attacks in detail, as well as the ways law enforcement has responded. What emerges from police files and interviews is a fragmented picture. The network, German investigators interviewed by WELT said, is less an organization than a scene, a collection of fellow travelers coordinating in an ad hoc fashion. 

Roles within the network are loosely divided. Some provide the ideological slogans: They write texts, deliver lectures and create the theoretical foundation for action. Others take on the operational side: small groups of siblings, childhood friends, kindred spirits. Meanwhile, left-wing publications outline grievances, justify attacks and, at times, describe in detail how to carry them out.

Authorities have been investigating attacks carried out by the so-called Volcano Group since 2011, but so far they have little to show for it. Figures that they associate with the network turn up in connection with one attack, fade out of sight, then reappear after another. Investigators trace a series of escalating protests and attacks that have culminated in the sabotage operations against the grid in Berlin. 

In May 2015, a group calling itself Capulcu — Turkish for marauders, a term adopted from the 2013 Gezi protests in Istanbul — published a 58-page booklet for download. Titled “Disconnect,” it was a call to fight the digitalization of modern life — by force, if necessary.

The authors accused the state and major corporations of waging a “technological attack” on society. New technologies like social media, they argued, are instruments of control. The response, they suggested, must be resistance — including sabotage. They wrote of “storming machines” and disrupting the “informational nervous system” with attacks on data cables and digital infrastructure.

Among the authors was a man known by several names, including his real one: Guido Arnold, a trained physicist who researches “biopolitics” at the Duisburg Institute for Language and Social Research. What sounds academic, investigators say, is also part of a political project. German security officials are convinced that what Arnold writes and posts online, or lectures about at left-wing centers in Germany and Switzerland, serves as inspiration and instruction for saboteurs.

Arnold did not respond to written requests for comment. In an interview with the daily German newspaper taz, he dismissed the idea that he was the leading thinker of the Volcano Group and described himself as a victim of a smear campaign. Asked if he had any affiliation with the group, he answered: “Why should I?”

In April 2020, Capulcu published a denunciation of an app the government hoped could be used to track Covid-19 infections. The activists saw it as an instrument of surveillance. Anyone who shares their data, they argued, risks ending up in the sights of law enforcement. “Where there’s a trough, the pigs will come,” wrote the group on the left-wing website Indymedia, referring to the police.

The app was developed with the help of the Heinrich Hertz Institute, a research institute. Nine days after the denunciation was published, a passerby in Berlin noticed smoke rising from a construction pit. A power cable had caught fire. Not long later, a claim of responsibility appeared on Indymedia. The attack, it said, was aimed at “a data line to the Heinrich Hertz Institute.” The action, it added, was directed against the “henchmen of new state techniques of domination and of the social technological attack.”

In mid-August last year, Arnold gave a lecture at the Berlin activist venue “Lunte.” In it, he railed against a “far-right tech oligarchy,” “destructive AI bullshit,” billionaires Elon Musk and Mark Zuckerberg, quoted Zuckerberg’s call for more “masculine aggression” and urged resistance against an “authoritarian project for the future.” These projects, he said, must be attacked “directly and immediately.”

A month later, the power pylons in Berlin were on fire.

Asked by WELT whether there was any link between his writings and the acts of sabotage, Arnold did not reply. In his interview with taz, he acknowledged the analyses provided by Capulcu could inspire “a desire to take action.”

“When we see the speed at which this development is progressing, it’s clear that we have to sabotage this technocratic ideology of the future,” he said. “But that doesn’t necessarily mean thinking about burning data centers. It can also simply mean delegitimizing this ideology and trying to undermine its foundations. There are many, many ways to counter this bleak vision of the future.”

Cat and mouse

The network’s loose structure has frustrated investigators seeking to thwart it, as even small cells learn from each other’s mistakes.

In the summer of 2017, far-left militants from across Europe — anarchists from Italy, radical environmentalists from France, German Marxists — converged on Hamburg to protest the G20 summit taking place in the city. They scouted targets and hid stones, fireworks and spare clothes. Cars and storefronts burned. The police struggled in vain to regain control. Almost miraculously, nobody was killed.

A year later, authorities got wind of a planned series of arson attacks — including one on the home of a Hamburg senator. Police identified three suspects. They lived in a shared apartment plastered with anti-police and anti-state posters. State security officers observed the trio, including through a camera hidden in a Coke bottle across the street from a left-wing squat that one of the suspects was known to frequent.

On the second anniversary of the G20 riots, investigators moved in. In a park in Hamburg, they arrested the three suspects. In a backpack, they found gasoline, barbecue lighter fluid, gloves and a list of potential targets. In November 2020, after a trial marred by attacks and sabotage attempts, the three activists were sentenced to prison terms of just under two years.

An anarchist magazine called Zündlumpen broke down what went wrong for the activists. Published in Munich, Zündlumpen is known for offering instructions for sabotage — how to disable streetlights without leaving DNA evidence, for example. Sometimes it consists of only two pages, densely printed in black and white. This time it ran more than 170 pages.

In this issue, published in September 2021, the anarchists studied the police the way a soccer coach studies their next opponent. They analyzed their own side’s mistakes and how to eliminate them.

After detailing how investigators tracked down the would-be arsonists, the authors praised them for traveling by bicycle. “The speed can be adjusted, public transportation can be used in between, and it is easier to determine whether you are being followed,”wrote the authors. But they chided the group for taking the same routes too often, making things too easy for police surveillance teams. “It is always worth planning enough time for detours, observations and self-checks.”

Investigators suspected the magazine’s authors were not mere commentators. Munich prosecutors believe people linked to Zündlumpen are behind arson attacks on forestry machines, wind turbines, concrete mixers and dozens of police vehicles. In April 2022, police accused three people of being behind the anarchist magazine and placed two of them in pretrial detention.

In March 2025, a senior public prosecutor filed charges against them — accusing them, among other things, of founding a criminal organization. But by the end of the year, part of the case collapsed. A regional court ruled that the evidence against one of the suspects was too thin. That individual would later be suspected by the Berlin Public Prosecutor’s Office of participating in the Johannisthal arson attack.

According to German law, neither journalists nor authorities can disclose the identities of suspected perpetrators. WELT was unable to contact the three individuals authorities believe are behind Zündlumpen.

Power failure

The attacks were getting bolder.

In March 2024, a power pylon near the construction site of a Tesla gigafactory was set on fire, halting production for days. Investigators zeroed in on a Berlin-based cell that included a man they believed was linked to the Hamburg riots and several arson attacks.

Security authorities placed tracking devices in vehicles, but the group discovered the devices and removed them. The police received a tip about an imminent attack on a parking site where Tesla was storing its vehicles. A hundred police officers positioned themselves in a nearby patch of forest, but the masked suspects fled.

A few days later, suspected saboteurs at a campsite near the Tesla site were seen handling jerrycans, filling bottles and practicing throws. But whatever they might have planned, they didn’t go through with it. Nobody was arrested.

Then came the attacks on Berlin’s power grids in September 2025 and January 2026.

The January attack resulted in the biggest blackout in Berlin since World War II. The first to notice it was the staff in the grid operator’s control center, notified when 16 automatically generated fault messages arrived on their phones. The sheer quantity of alerts did not fit an ordinary power outage. Workers initially categorized the situation as a technical malfunction, according to internal logs reviewed by WELT.

At 6:14 a.m., the assessment changed. A fire had broken out beneath a cable bridge over the Teltow Canal. Several power lines were in flames. Emergency crews on the scene reported explosions. As firefighters battled the blaze, electricity went out across large parts of the city. Those in charge triggered a staff alert level 3 — the highest level, a “major emergency incident.”

According to the logs, 45,000 households and around 2,000 businesses were affected, including five hospitals, three with emergency care units. Also hit were 66 care facilities and numerous people receiving care at home — including individuals like ALS patient Andreas Thomsen, who cannot breathe without electricity.

For the authorities, this attack was a turning point. “We need to intensify the fight against left-wing terror,” said German Interior Minister Alexander Dobrindt in the weeks after. Internally, his language was harsher. Authorities had been tracking attacks by the so-called Volcano Group since 2011 — and they still had no solid leads. Dobrindt said he was extremely dissatisfied.

A confidential analysis by Germany’s Federal Criminal Police Office found 321 incidents of sabotage nationwide last year, including a sharp uptick in the third quarter, when authorities logged 94 cases. Early targets included military and police facilities and rail infrastructure, followed by an increase in attacks on the energy grid.

Data compiled from Germany’s federal states suggests most identified suspects are linked to the far left. In the state of North Rhine-Westphalia alone, the state Interior Ministry attributes 425 out of 445 attacks on the electricity and energy grid since 2019 to perpetrators motivated by left-wing ideology. 

While Dobrindt has publicly pointed to Moscow as being behind the attacks, police have not been able to provide proof of the Kremlin’s involvement. “One theory is that so-called low-level agents are being deployed — meaning foreign powers make use of approachable or coercible individuals on the ground to carry out espionage or sabotage,” said Dobrindt in a recent interview.

However, an internal Federal Police analysis from autumn 2025 struck a more sober note: “So far, police investigations have not, in any concrete case, been able to substantiate state direction or corresponding activities, nor provide proof of the involvement of intelligence services or foreign state actors in the possible reconnaissance of critical infrastructure, military facilities or defense companies.”

Police raids

A few weeks after the blackout, the Federal Criminal Police Office and the federal prosecutor went on the offensive: They announced a reward of €1 million — 40 times higher than what was offered for Daniela Klette, a suspected terrorist accused of prominent attacks in the 1990s.

The Berlin blackout and its consequences also kicked off a debate on left-wing online platforms. Some older activists argued it was a step too far: They had wanted to cause a “disturbance of normality,” not its “destruction.” Many younger people, by contrast, said they wanted to continue the attacks.

Investigators tapped phones but found little that was truly incriminating. In late March, authorities carried out coordinated raids across Berlin and the rest of the country. More than 500 police officers searched apartments, meeting spots and an anarchist bookstore. The targets were strictly secret. The fear of leaks was so great that even officers inside the State Criminal Police Office were led to believe the operation concerned escalating gang violence in Berlin.

But in the end, what they uncovered was mostly just books. In one location, officers first rammed open the door, then lifted a window off its hinges. For a brief moment, onlookers could glimpse inside the room. Masked police officers were standing in front of plain wooden shelves full of books and pamphlets. A box was labeled “prisoner mail.” On one of the shelves, the corner of a booklet could be seen. “Disconnect,” the cover read.

Again, nobody was arrested.

Speaking in March, a few days before the raids, Thomsen — the man whose ventilator nearly ran out of battery — described the gratitude he feels to those who rescued him.

“They did something extraordinary,” he said. “Otherwise, I wouldn’t still be here.” He showed photos on his phone from before his disease began taking away his mobility. In one, he’s riding the bicycle he once used to commute to his law office. In another, he’s with his son at the barber. 

His son is now seven, he said. “He is the reason I want to keep living.”

Lennart Pfahler and Philipp Woldin are reporters for WELT. Alexander Dinger is WELT’s investigations editor.

The Axel Springer Global Reporters Network harnesses the resources of the company’s newsrooms to publish ambitious scoops, investigations, interviews, opinion pieces and analysis. It allows journalists — including those from POLITICO, Business Insider, WELT, BILD, Onet and Fakt — to collaborate on major stories for an international audience of hundreds of millions across platforms: online, print, TV and audio.