South-west Berlin households and businesses could face days without electricity following a fire that damaged power lines, in what officials have labelled a politically-motivated attack.

The blaze erupted on Saturday, January 3, on a cable bridge near the Lichterfelde power plant, according to local authorities. On Sunday, January 4, city officials attributed the fire to "left-wing extremists."

The incident left over 45,000 households and 2,200 businesses across four districts without power, disrupting heating and internet services as well. Authorities are treating the incident as potential arson and drawing parallels with a similar power outage in south-east Berlin last September, for which radical activists claimed responsibility, The Mirror reports.

A letter claiming responsibility for Saturday's incident is currently under investigation for its authenticity. Berlin's Mayor Kai Wegner told a German news agency that the culprits were "clearly left-wing extremists," adding: "It is unacceptable that once again clearly left-wing extremists have attacked our power grid and thereby endangered human lives,".

The city's Senator for Economic Affairs, Franziska Giffey, described the incident as "a particularly severe power outage", impacting tens of thousands of households and businesses, including care facilities, hospitals, social institutions and companies.

By Sunday, power had been restored to thousands of households, however, many others are expected to remain without electricity until Thursday, according to authorities.

The restoration efforts have been hampered by snowy weather and freezing temperatures, exacerbating the situation for those affected.