Twenty-two people were injured when several decks on a three-story building collapsed during a firefighters’ event on Saturday in Wildwood, New Jersey.

The horrific event occurred at 6 p.m. in the 200 block of East Baker Avenue when three levels of deck on a residential building fell on top of each other during the annual New Jersey Firemen’s Convention. Reports said at least three children were also injured as a result of the collapse.

The New York Post reported:

Shocking video captured at the scene shows at least a dozen firefighters in full turnout gear standing around a huge slab of fallen deck as they work to free anyone trapped underneath. Most of those watching on also wear t-shirts and hats marking local fire units attending the event that attracts thousands of current and former firefighters to the resort town.

“I heard this noise, so I turned and looked and saw the whole thing caving in,” said Joann Devito, a witness who was sitting on her porch across the street when the tragedy occurred. “I saw two women running and screaming. It was horrible.”

Reports said 21 people were rushed to a local hospital after the collapse and eleven of the victims, including the three children, were released before 10 p.m. that night. Reports said one victim was medevaced to a trauma center for treatment. However, no fatalities have been reported so far.

Witness Gail Ivins told reporters that she watched as the first deck gave way, then the second.

Ivins commented:

There was a far section that was still on the building. There was a 2-year-old little girl still on the deck all by herself on that little corner and another lady on the third floor. We were yelling to the girl to stay away from the edge. That one came down, but it went slowly. When it slid off, there were men there to grab [her]. The third floor section came down after that with the lady standing on it. She slid off and right onto the sidewalk.

Reports said authorities are currently investigating the initial cause of the collapse.