Millions of Greeks were temporarily left without electricity yesterday, stores were forced to shut, people got stuck in elevators, traffic jams were caused by failing signals and two trams in Athens collided due to an ongoing strike by Public Power Corporation (PPC) employees that has deprived the country of much of its normal power supply. PPC was forced to adopt rolling power cuts across Greece yesterday in a bid to make up for the reduced output from its power plants and try and prevent a nationwide blackout. More than a third of PPC’s normal electricity output was lost due to the strike by workers, who have been taking industrial action since Monday. The Athens court of first instance is due to decide today whether the strike is legal or not. Many neighborhoods in Athens and Thessaloniki were left in darkness last night as their power was cut off for about two hours. Cuts earlier in the day had caused a number of problems. The fire service received some 900 calls from people trapped in elevators over the last two days. Hundreds of shops were forced to close as they were unable to operate cash registers and other equipment. Concerns were raised about the safety of food being stored in refrigerators and freezers at supermarkets and other stores. Two trams collided in southern Athens when a power cut resulted in the failure of the automatic track switching system. Two passengers were slightly injured and both trams were badly damaged in the collision. The power cuts also meant traffic lights were out of operation in Athens and Thessaloniki, leading to chaos on the roads of both cities. The rolling power cuts were due to end at 10 p.m. last night but they may have to be reintroduced today if the workers continue their protests, which target the government’s planned pension reforms. The walkout by workers has led to 16 PPC power plants being shut down.