BERLIN: Berlin’s mayor said on Monday the German capital’s core infrastructure ​needed better protection two days after an arson attack on a power station left tens of thousands of people without power.

The far-left Volcano activist group claimed responsibility for the attack which also shut down mobile phone connections, cut heating during freezing weather, stopped trains and forced hospitals to switch to back-up generators.

“Left-wing terrorism is ‌back in Germany ‌with increasing intensity,” Interior Minister ‌Alexander ⁠Dobrindt ​told the ‌Bild newspaper in an interview.

Volcano, which says it is against the energy industry’s use of fossil fuels, has claimed several attacks in Berlin and the neighboring Brandenburg region.

“There will be talks which we have to have with the federal government about how we can better protect our critical infrastructure, ⁠especially in the area of the capital,” Berlin mayor Kai Wegner told ‌a news conference.