A massive power outage struck the Swiss city of Zurich, electric officials have confirmed, adding that the city center lost electricity and traffic was halted. Almost an hour after the blackout, the power was back.

The Zurich Electricity company (EWZ) tweeted that the blackout took place shortly before 2pm local time (12:00 GMT).

The company added that two transformers had been shut down due to “unknown reasons.”

The lights were off on Zurich's main downtown street, Bahnhofstrasse, Swiss 20 Minuten newspaper reported.

Several shops had increased security measures, according to the paper.

The affected area included Bahnhofstrasse, one of the world's most expensive and exclusive shopping avenues, as well as Schanzengraben and Wiedikon districts, EWZ said.