NEW YORK (CBSNewYork) -- A building collapsed in Brooklyn on Wednesday, and surveillance video shows several people running for their lives.
It happened just before 5 p.m. and hours later, crews were in the process of demolishing the building.
One person got out on their own before the FDNY arrived. That person was taken to the hospital for minor injuries.
The three-story building was a gym that, pre-pandemic, would have likely had dozens of people inside.
Exclusive surveillance video shows a sunny and busy afternoon on Court Street in Carroll Gardens quickly swallowed by a cloud of smoke with pedestrians running for cover.
That smoke was the aftermath of the building at 348 Court Street, known as Body Elite Gym, suddenly collapsing.
Bob Krissnanand was taking out recycling from the health store next door. He says the building crumbled in 30 seconds.
"All of a sudden I saw something, the building coming down and after that I don't know what happen. I run in the middle of the street. I was covered with, you know. I couldn't see anything," he told CBS2's Lisa Rozner.
"It was just a cloud of dust," said another man who also works next door.
"We had to close all the doors. We had our doors open, close right away. Bring all our tables in," restaurant owner Marco Chirico said.
"I thought it was an explosion," one witness said.
The FDNY says it was not an explosion and is investigating the cause, but a stop work order had been issued on construction there just a few weeks ago.
"We do know that there were some issues with the facade. There was a bulge in the exterior wall, and that was one of the things that they were here with, get a stop work order because of the way they were performing the work," said Timothy Hogan, deputy commissioner of enforcement for the Department of Buildings.
Aerial footage from the NYPD shows how the roof slid to the side and floors on a diagonal.
Online records from the Department of Buildings show around a dozen complaints have been made to the city about its "structural stability" every few years dating back to the '90s.
A gym employee who was delayed getting to work believes the latest construction to beautify the walls by installing more windows is not the cause.
"There's steel reinforced beams everywhere and there would be no reason to question the integrity of the structure of it," the employee said.
"I'm glad that gyms weren't allowed to reopen because if it was, it could have been a lot worse. A lot worse," Carroll Gardens resident Jeannie Jackson said.
The city's engineers say the debris pile that is left is not in danger of further collapse and they are monitoring the stability of the standing south wall.
The FDNY has evacuated neighboring building until it can determine that it is safe.
The property that collapse is owned by Union and Court Realty Corps, but CBS2 was not able to reach anyone at the company for comment.
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