
Cheers were heard across large swathes of Manhattan as the lights flicked back to life after an hours-long outage caused chaos in the city.

The blackout was reported in Midtown, Times Square, Hell’s Kitchen, and other parts of Upper Manhattan, with subway stations affected and street lights out.

The New York City Fire Department said the cause of the outages, which left more than 73,000 Con Edison customers without power, was a transformer fire which started at West 64th Street and West End Avenue on the Upper West Side.

No deaths or injuries were reported due to the blackout, which officials said began at 6.47pm and darkened a stretch of the city from West 42nd Street to West 72nd Street, 42 years to the day from a major 1970s blackout that sparked rioting and looting.

'Members are responding to reports of numerous stuck elevators that are occupied, but there are currently no patients reported,' the department said on Twitter.

Shortly before midnight, Mayor Bill de Blasio confirmed all power had been restored and shouts of celebration could be heard and people turned their air conditioners back on amid the stifling heat.

One video shows people crossing the street in the dark, but raising their arms and cheering as the lights turned back on.

Let there be light: People are seen cheering as they cross the street as the lights flick back on following the hours-long outage

Shouts of celebration could be heard as the lights came back on in the streets of New York City following the blackout

The blackout was reported in Midtown, Times Square, Hell’s Kitchen, and other parts of Upper Manhattan, with subway stations affected and street lights out

A large section of Manhattan's Upper West Side and Midtown neighborhoods are seen in darkness from above

Large parts of Times Square were without power and many of the enormous billboards were black following the outages

The screens in Times Square in New York went black following the power outages but it did not stop people taking photographs of the iconic sight

People are seen sitting waiting at the East River Ferry Dock while trying to find an alternative route home on Saturday night

Subway riders took to Twitter to share pictures of darkened stations during the blackout. Many people were stuck on trains when the power went out

People are seen waiting inside Columbus Circle subway station following the widespread blackouts in New York on Saturday

Customers are seen in dark restaurants with on candles on their tables. The outage extended from Fifth Avenue west to the Hudson River, and from the west 40s north to 72nd Street

A subway station is in the dark during the outages. People reportedly used the flashlights on their phones to guide their way

An area leading to the C and E trains at the 50th Street Subway Station is seen dimly lit during the power outage

Stairs leading down to the C and E trains at the 50th Street Subway Station are pictured abandoned and dark during the blackout

Residential and commercial buildings are seen in darkness during the outages in New York City on Saturday night

A map shows the locations of the power outages in Manhattan on Saturday evening

A Jennifer Lopez concert at Madison Square Garden was halted and disappointed fans had to be evacuated.

Concert-goers were met with darkness about four songs into her set about 9.30pm. The arena was later evacuated.

The superstar posted a video on Instagram and wrote: 'Devastated and heartbroken that I can’t perform for all of you tonight. We will make this up to you, I promise! I love you!!'

She said in a video: 'They just told me to get off stage. I was just waiting there, obviously all the power went out in the city and here at Madison Square Garden while we were in the middle of our show.

Jennifer Lopez shared a video on her Instagram apologizing after her show had to be canceled due to the power outages

Jennifer Lopez is seen before and after the lights went out at her show in Madison Square Garden on Saturday night

J.Lo's dancers are seen on stage moments before Madison Square Garden went dark when the power outages hit

'They are asking everybody to evacuate very slowly and calmly. Obviously we are going to reschedule this show.

'I am obviously heartbroken and devastated. I love you. I'm so sorry that this happened in the middle of our moment.'

Shortly after 1am on Sunday morning, she tweeted: 'ANNOUNCEMENT: Gonna take more than a city-wide blackout to shut us down! Rescheduling the show for Monday night!'

Officials at Penn Station said they were using generators to help keep the power on. Many of the enormous billboards in Times Square were black and power was out in much of the Rockefeller Center.

Videos emerged on Twitter of subway riders trying to navigate their way around darkened stations, several of which were without power and were being bypassed by trains.

Social media users shared videos of diners eating in restaurants with just candles for light, and people reported being stuck in elevators in the city's high rise apartment buildings.

The outage darkened a stretch of the city from West 42nd Street to West 72nd Street, 42 years to the day from a major 1970s blackout that sparked rioting and looting

Commuters use their phones as flashlights during the outages in a city that usually never sleeps and the lights never go out

A store owner in Times Square sits outside during the outage. Stores no doubt lost out on plenty of sales on a busy Saturday night

Crowds of people walk along a dark street in Midtown. Many people had to find alternative routes home due to problems with the subway system

A billboard in Times Square is seen without power on Saturday evening. It was an unusual sight for New Yorkers who are used to the bright lights

People are seen waiting in line for buses because the train service was down. One commuter said he was stuck in a subway car for more than an hour

Customers at the AMC Lincoln Square 13 movie theater are seen leaving after it lost power on Saturday night

The usually bright skyline was mostly dark and gloomy on Saturday night. The cause of the outages was a transformer fire

New York Gov. Andrew Cuomo said in a statement that although no injuries have been reported 'the fact that it happened at all is unacceptable,' and the Department of Public Service will investigate the blackout.

He said he was sending 100 State Police officers and some National Guard troops to the city to help with traffic control.

De Blasio told CNN said he had spoken with the police commissioner and the deputy commissioner who handles counterterrorism.

'From what we're seeing at this moment, this is simply a mechanical problem and one, again, that sounds like it is addressable in a reasonable period of time,' de Blasio said.

City Council Speaker Corey Johnson wrote on Twitter that the Con Edison substation on the West Side had a 'major disturbance' and that the utility was working on fixing it.

Most Broadway shows were cancelled Saturday night, but in true New York style, some of the performers exited the theaters and sang in the streets for disappointed ticket-holders.

The Upper West Side was dark after a transformer fire caused a power outage. The temperature was warm, above 80 even as the sun set, but not as steaming as Manhattan can get in July

Tired children and adults watch policemen and firemen gather at their apartment building following the blackout

Casts from Come From Away, Waitress and Hadestown (pictured) performed for audiences waiting to be admitted

Twitter user @MarlinPie shared a video of performers outside Carnegie Hall. 'Performers were evacuated outside of the building but they continued their performance,' he wrote

Casts from Come From Away, Waitress, Hadestown and Rock of Ages performed for audiences in the streets.

Emily Totero, 30, planned to bring out-of-town guests to see Moulin Rouge, but once they got to the theater district, they saw the power go out.

'You could see all the theater lights across the street, all the marquees went out. That's what we noticed first,' she said.

With some stations and traffic lights dark, many residents and visitors alike took to the streets and walked, according to social media posts, many of which had the hashtag #blackoutnyc.

Jeff O'Malley said he was stuck in a subway car for more than an hour.

'We were stuck for about 75 minutes,' said the 57-year-old consultant. 'It's completely dark (in the station); people were coming up using their flashlights on their phones.'

Firefighters are pictured responding after widespread power outages were reported in parts of Manhattan

The signs at the iconic Radio City Music Hall in midtown are out following the power outrages

Power was out in much of Rockefeller Center. Firefighters are seen entering 75 Rockefeller Plaza

Twitter user Lizzy Aimée shared a video of firefighters entering her apartment building and wrote: 'Can't get up to our apt and people are stuck in the elevators!'

Multiple civilians stepped into always-busy intersections to help direct traffic snarled by the lack of traffic lights.

One middle-aged man in shorts and a red tank-top managed the flow of vehicles at one junction for at least 45 minutes, drawing plaudits on social media.

In a photo on Twitter taken after darkness fell, one person was seen directing traffic in the Hell's Kitchen neighborhood with a toy light saber.

The outage occurred on the 42nd anniversary of a New York blackout that crippled nearly the entire city during a heat wave on July 13, 1977.

Power was not restored until the next day.