Authorities in NY on Thursday said they were looking into a "transformer incident" following reports of an explosion.
However, this did not stop spectators from sharing videos and pictures of the flashing light and speculating on social media.
NYPD is investigating a possible transformer explosion at the ConEd plant in Astoria.
The Federal Aviation Administration (FAA) shut down nearby LaGuardia for an inspection after the downed transformer caused power outages at the airport, while the NYPD confirmed that no one was injured in the incident.
The Metropolitan Transit Authority said power outages were affecting 7 trains.
CBS Newspath senior producer Heather Scott reported from Astoria that the sky turned "super bright blue" and it "looked like daylight outside".
Around 11 p.m., the airport tweeted power was restored in the temrinals with outgoing and incoming flights resuming.
It comes just days after an "explosion" was spotted in the skies above California.
Minutes later, the New York Police Department Chief Terence Monahan said the incident was under control, and said no injuries were reported.
"I wish the blue sky in NY was aliens and not a power plant on fire", one Twitter user wrote. On Twitter, officials apologized to dozens of alarmed customers, saying they "are aware of this situation". The MTA had to check system signals to ensure there were no power issues or surges. The utility said in a statement early Friday that an electrical fault on the 138,000 volt equipment caused a sustained electrical arc flash but the "affected equipment was isolated to a single section within the substation".
A video by The Weather Channel shows a 2012 explosion at the same power plant produced the same result.
"Once we saw people running, we chose to get out", he said.