Smoke could be seen pouring from two of the five manholes shortly before 10 a.m. Just over an hour later, as gas and fumes built up, one of the manholes exploded.
Citizen App users captured some of the scene.
"I saw the fire truck, they started coming down and then I noticed the other manholes start smoking," Ryan Jaglal said. "And then I heard a loud sound - BOOM - and everybody started running this way."
People working in nearby buildings say they lost power after feeling and hearing the explosion.
"It woke me up, so it was a really loud explosion and it just kind of came out of nowhere," Eva, a neighborhood resident, said. "It was so, so loud, and I didn't know what was going on. It's New York, so you think the worst, and I look outside and there was smoke all over."
Five firefighters and the building super suffered minor injuries.
Officials evacuated two buildings, including the Chelsea Day School, along East 32nd Street because of high carbon monoxide readings. Several other buildings were monitored, and Con Edison Emergency crews cut power in the area.
Update: @FDNY says a pair of smoking manholes in #midtown led to gas build-up and resulting explosion in cellar of 6 East 32nd Street. 3 firefighters injured, 1 building super, none of them life threatening. #breakingnews pic.twitter.com/GDqvu4XxQx— Joe Torres (@joetorresABC7) April 24, 2019
The incident shut down traffic on East 32nd Street from Sixth Avenue to Madison Avenue and on Madison Avenue from East 31st Street to East 33rd Street.
Con Edison said several buildings on East 32nd Street would lose power while crews de-energize the area. Con Ed does not know how long power will be out while they work on wiring and infrastructure under the roadway.
The cause of the three-alarm incident remains under investigation.
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