NEW YORK (AP) — On the anniversary of a 1977 blackout that left most of New York City without power, a massive power outage on a hot Saturday night in Manhattan preemptively brought the curtain down on Broadway shows and packed streets with people wielding cellphones as flashlights amid a cacophony of sirens and horns from stalled traffic.

Underground, the scene was similarly in disarray as the blackout affecting 73,000 customers for more than three hours hit the subway system. Con Edison CEO John McAvoy said a problem at a substation caused the 6:47 p.m. power failure, which stretched 30 blocks from Times Square to 72nd Street and Broadway and spread to Rockefeller Center. Electricity was restored to customers and businesses in midtown Manhattan and the Upper West Side by around midnight, according to a statement from the utility.

McAvoy said the exact cause of the blackout would not be known until an investigation is completed.

The outage affected the entire subway system, closing four Manhattan stations to the public — Columbus Circle, Rockefeller Center, Hudson Yards and Fifth Avenue at 53rd Street. But Metropolitan Transportation Authority spokesman Maxwell Young said train operators were able to manually change the signals and bring at least one car into stations so passengers could disembark.

New York City’s Emergency Management Department said the A, C, D, E, F, M, 1, 2, 3, 4, 5, 6 and 7 trains had resumed running in both directions by around 2 a.m. Sunday, following service disruptions from the blackout. Multiple street lanes between the Hudson River and Fifth Avenue had also reopened by 1:30 a.m.

The temperature was in the low 80s as the sun set just before 8:30 p.m., treating those who had streamed into the street to one of the city’s famed “Manhattanhenge” sunsets. While hot, the temperature didn’t reach the highs of Manhattan in July, which often challenges the city’s power grid.

New York Gov. Andrew Cuomo praised emergency officials for their response to the blackout and said no injuries were reported, but called the outage “unacceptable.”

“You just can’t have a power outage of this magnitude in this city” Cuomo said. “It is too dangerous, the potential for public safety risk and chaos is too high, we just can’t have a system that does that, it’s that simple at the end of the day.”

New York City Mayor Bill de Blasio was campaigning on the presidential trail in Iowa when the power outage struck. His press secretary, Freddi Goldstein, tweeted just before 10 p.m. that de Blasio cut short his Iowa visit and was headed back to the city.

The mayor commended New Yorkers for handling the blackout “with that trademark NYC grit and toughness” in a tweet.

Screens in Times Square are black during a widespread power outage, Saturday, July 13, 2019, in the Manhattan borough of New York. Authorities say a transformer fire caused a power outage in Manhattan and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

For hours before the power flicked back on, doormen stood with flashlights in the darkened entrances of upscale apartment buildings along Central Park West, directing residents up flights of stairs, with all elevators out. Police and deployed troopers directed traffic at intersections, while people in the neighborhood known as Hell’s Kitchen took it upon themselves to direct traffic as stoplights and walking signals went dark.

In the theater district, marquees darkened just before evening performances were set to begin. Most Broadway musicals and plays canceled their Saturday evening shows, though some cast members staged impromptu performances in the street.

Jennifer Lopez’s concert at Madison Square Garden was cut short in the middle of her fourth song of the night, although officials at Penn Station below used backup generators to keep the lights on. Madison Square Garden, Carnegie Hall and the Lincoln Center for the Performing Arts were all evacuated. Lopez later tweeted that she would reschedule the stop on her “It’s My Party” tour for Monday night at the same venue.

Screens in Times Square are black during a widespread power outage, Saturday, July 13, 2019, in the Manhattan borough of New York. Authorities say a transformer fire caused a power outage in Manhattan and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

Screens in Times Square are black during a power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

Pedestrians looks at their cellphones during a power outage in midtown Manhattan, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

A man makes his way through a dark Times Square during a power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

A subway station is in the dark during a widespread power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens, darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

Stairs leading down to the C and E trains at the 50th Street Subway Station are dimly lit during a power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

An entrance to the C and E trains at the 50th Street Subway Station is dimly lit during a power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)

Traffic lights hang without power in Times Square during a power outage, Saturday, July 13, 2019, in New York. Authorities were scrambling to restore electricity to Manhattan following a power outage that knocked out Times Square’s towering electronic screens and darkened marquees in the theater district and left businesses without electricity, elevators stuck and subway cars stalled. (AP Photo/Michael Owens)