Police are investigating an initial suspicion of arson following the power failure at the Tesla car factory near Berlin, a spokesman told dpa upon request.
In the early hours of Tuesday a burning electricity pylon caused a major power outage in the region near the factory.
Production at Tesla's only European plant in Grünheide came to a halt, and the factory was evacuated.
"We are investigating the initial suspicion that it was deliberate arson," said the police spokesman. According to the police, the State Criminal Police Office has begun an investigation.
The electricity pylon in question was standing freely in a field and was not fenced in. Tesla said that an arson attack was assumed and referred to information from the relevant authorities.
A report by tabloid newspaper Bild suggested that the fire was caused by environmental activists who are occupying part of the forest that Tesla plans to use for the expansion of its factory site.
The authorities did not initially comment on a possible connection with protests around the site when asked.
Tesla said that all measures had been taken to secure the production facilities. After consultation with the electricity provider EDIS, Elon Musk's company does not expect production to restart quickly.
According to the police, the fire brigade was called at around 5:15 am (0415 GMT) and began extinguishing the fire.
A police helicopter was also deployed in the morning after the alarm was raised about the fire.
Around 80 to 100 activists have been occupying part of the forest near the factory since Thursday in opposition to the company's expansion plans. The activists plan to hold out as long as possible in the 10 or so tree houses they erected.
A citizens' initiative from Grünheide is also speaking out against Tesla's expansion plans and is showing solidarity with the squatters.
Tesla has been manufacturing electric cars in Grünheide for almost two years. According to the company's latest figures, around 12,500 employees work there.
Environmentalists criticize the fact that the site is located in a water protection area, among other things. In a public consultation in Grünheide, the majority of residents said they oppose the expansion plans.
