Berlin/London CNN  —  Power supply to Tesla’s factory near Berlin has been cut following an arson attack on a high-voltage electricity pylon nearby, a German official said Tuesday. “If the initial findings are confirmed, this is a perfidious attack on our electricity infrastructure. This will have consequences,” Michael Stuebgen, the interior minister for the state of Brandenburg, said in a statement. He said power supply to the Tesla plant as well as nearby villages had been cut off. German public broadcaster ZDF reported that the factory had been evacuated and its workers sent home. It was unclear when production would restart. CNN has contacted Tesla (TSLA) for comment. The carmaker’s huge plant — located about 30 kilometers (18 miles) southeast of the German capital — is its only one in Europe and is currently capable of producing 375,000 electric cars a year. Unknown perpetrators deliberately set fire to the pylon early on Tuesday morning, the German official said. “Thousands of people have been cut off from their basic supply and put in danger. The rule of law will react to such an act of sabotage with the utmost severity,” he added, noting that a criminal investigation into the incident had begun. It is unclear if the arson attack is connected with ongoing protests against a planned expansion of the Tesla factory. Since Thursday, around 80-100 environmental activists have been occupying part of a forest near the plant, which Tesla wants to clear for the expansion, ZDF reported Tuesday. “Nothing can yet be said about the perpetrators, so I would caution against premature speculation,” Stuebgen said. Last year, Elon Musk’s company lodged an application to ramp up the factory’s production capacity to 1 million electric vehicles a year, which would make it Europe’s biggest car plant. But in February, local residents voted against a motion to clear enough forest for Tesla to expand the site, leaving it to local authorities to decide how to proceed, according to Reuters.