Con Edison said on Twitter an electrical fire at a substation in the Astoria section of Queens caused a transmission dip in the area.
"You felt it in your chest, the explosions, and the night sky turned an electric blue".
But despite the eerily glowing color, an alien invasion it was not. The MTA has power, "but there are delays on the 7 train", he tweeted.
"There was a boom and a bang and a flash of light", said Jim Long, a spokesman for Fire Department New York. No injuries have been reported, but some areas of the city have experienced blackouts, including the LaGuardia Airport.
PIX11 said NYPD was investigating a transformer explosion at Astoria East and North Queens Con Ed power plant.
According to the utility outage map for Con Edison, there were only 76 who were said to have lost power.
Karol Markowicz said: 'Wtf if this insane bright blue light over Brooklyn?!?'
A video by The Weather Channel shows a 2012 explosion at the same power plant produced the same result.
However brief the fire was, its effect was large - the bright blue light was clearly visible across other boroughs in New York City, and as far as New Jersey.
New Yorkers were shocked and amazed by an eerie blue light that took over the night sky in Astoria, Queens, Thursday night.
Police said the fire was "under control", as confirmed in a tweet, and the 144th precinct asked citizens to avoid 20th Avenue and 31st Street.
"*Not* aliens. Blown transformer at Queens Con-Ed facility", Eric Phillips, the mayor's press secretary, tweeted, "Scattered power outages, including LGA".
Because all FAA facilities at La Guardia are on generator power there was no interruption to air traffic control, FAA spokesman Greg Martin said.