The fire sparked a manhole explosion and sent flames shooting up the side of a 15-story building at Lexington Avenue and East 56th Street.
It was a chain reaction. After the manhole blew, a minivan parked a few feet away exploded.
"You can see that the car was completely in flames," eyewitness Jody Revenson said. "The trees went in flames, there was a bicycle there, no longer...that went in flames. Black smoke up to the top of the building. I immediately called 911."
The fire quickly spread to the scaffolding above and a second-floor apartment.
"It started in the transformer vault, which was underground," FDNY Deputy Chief Jim Hodgens said. "So in all likelihood it was electrical in nature."
He added that it possibly could have been caused by the heat.
The FDNY says the apartment building briefly lost power, and a resident got stuck in the elevator on the 11th floor.
The smoke also trapped another resident in a ground floor laundry rooms, but no one was injured.
Con Ed says members of its management team responded to the emergency, as the fire comes almost a week since 8,500 utility workers were locked out.
Con Ed says transformer fires are common in the summer, when so many New Yorkers are trying to beat the heat.
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