A far-left extremist group, identifying itself as 'Vulkangruppe' (Volcano Group), claimed responsibility for an arson attack that caused a massive power outage in parts of southwest Berlin beginning Saturday, January 3, 2026. The attack, which involved setting fire to high-voltage cables on a bridge over the Teltow Canal near the Lichterfelde power station, plunged approximately 45,000 to 50,000 households and up to 2,200 businesses into darkness. This incident occurred amid freezing temperatures, dropping as low as -10°C at night, exacerbating the hardship for residents who were left without electricity and often heating. While the original article suggested a 'two-day power cut,' many affected areas experienced outages lasting up to five days, with full restoration for all customers not expected until Thursday, January 8, 2026. The widespread disruption also impacted critical infrastructure, including mobile phone services, public transport, several hospitals, nursing homes, and schools, forcing some evacuations. In response to the deliberate act, German federal prosecutors launched a terrorism investigation on January 6, 2026, citing charges including 'membership in a terrorist organization, sabotage, arson and disruption of public services'. Berlin's Interior Minister Iris Spranger and Mayor Kai Wegner explicitly condemned the attack as 'left-wing terrorism,' emphasizing that the perpetrators knowingly endangered human lives. The Vulkangruppe stated their actions were a protest against the fossil fuel industry and the expansion of artificial intelligence infrastructure, aiming to target the city's wealthier districts. This incident highlights Germany's vulnerability to such acts of sabotage, prompting calls for increased investment in critical infrastructure security.