Tens of thousands of Berlin residents expressed optimism on the restoration of power supply on Wednesday after a mishap at a construction site which plunged households and businesses into darkness.

City officials said a worker on a bridge renovation project accidentally severed a critical power connection around 2 pm (1300 GMT) on Tuesday, cutting off energy to the city’s eastern Koepenick district.

The outage affected more than 30,000 households and 2,000 businesses.

Schools and day care centres in the affected area were expected to stay closed on Wednesday while workers laboured to fix the situation.

“This is a demanding job that is simply going to take a little time. That’s why this blackout is taking significantly longer than previous power outages,’’ said a representative for power company Vatenfall.

Workers were hoping to have the electricity back on or around 3 pm on Wednesday.

Many of the affected buildings rely on electricity for their heat, meaning residents had to tough out a cold night, despite relatively mild daytime February temperatures this week.

Vattenfall said heat could only be restored to the 5,000 affected residences once the power is back on.

There is also a hospital in the affected region.

Emergency crews set up an additional power supply to help the hospital get through the night, while some patients in need of extra care were transferred to other facilities.

Police have been out on affected streets in extra numbers to help ensure order.

Many traffic lights were not working, and tram lines were unable to run without power.

Adding to the problems, neither landline nor mobile phones were working in the region. (NAN)

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