A power failure in New York has halted subway trains and trapped people in lifts.
The New York Fire Department said it was tackling a fire in an electrical transformer in Manhattan, the most densely populated of the city’s five boroughs.
Street lights and traffic lights have been put out of action.
The local energy company Con Edison said about 42,000 people had been deprived of power.
The cuts are affecting the Upper West Side of Manhattan between 40th and 72nd Streets between Fifth Avenue and the Hudson River, an area which includes the Broadway theatre district.
A number of Saturday night shows were delayed, with theatregoers left waiting in the streets outside venues.
The cast of the musical Hadestown entertained people waiting outside the Walter Kerr Theatre.
The Metropolitan Transportation Authority (MTA) advised travellers to avoid sub-surface trains, after some passengers were stranded below ground for over an hour.
“We were stuck for about 75 minutes,” Jeff O’Malley, 57, told Reuters news agency. “It’s completely dark, people were coming up using their flashlights on their phones.”
The electricity cuts come on the anniversary of a massive power failure in 1977 that plunged the New York skyline into darkness and triggered widespread looting and arson.