People in the neighborhood said they could feel their apartments shake as the blast shot glass across Broadway.
It all started just before 4 p.m. Sunday at Equinox on 2465 Broadway between 91st and 92nd Street.
CeFaan Kim was on the scene:
A group of men said they were exercising when the alarms went off and they were evacuated.
"We saw them all with gas measuring machines, and we smelled quite a bit of gas, too," one of the men said.
Fire officials say they also detected high levels of carbon monoxide.
When they arrived, they thought they were responding to an electrical fire in the basement. It turned out to be a ConEd transformer under the sidewalk, and the electrical malfunction caused the carbon monoxide leak.
"Gas is a very dangerous substance, and a spark can be caused by many things," FDNY Assistant Chief John Hodgens said. "Something as little as a telephone ringing or a light switch being turned on can trigger an explosion."
Luckily, the gym was already evacuated, along with three other businesses. Officials said 90 people were evacuated in all, including 15 residents.
Then, the doors and all the windows shook.
ConEd shut both the gas and electric to the gym, as well as gas on the entire block.
Nine buildings remain without gas Monday, and restoration is expected by the evening.
Looks like ConEd has shut off gas. FDNY going back in now. pic.twitter.com/bLy4ZTMvk0— CeFaan Kim (@CeFaanKim) November 26, 2018
The gym is next to a Petco, and officials said all of the animals inside the store were found to be safe.
No one was injured.
The Department of Buildings placed a full vacate order for Equinox due to the building's structural damage and broken glass windows.
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