The wall fell onto four workers at the Queens Boulevard site in the Elmhurst section just before 9:45 a.m.
Investigators are looking very closely at building procedures in the construction of the wall.
The wall of concrete blocks, 65 feet long and 20 feet high, came crashing down as construction workers were in the process of filling voids in the wall with concrete, investigators said.
The blocks buried two of the workers.
"Two were on the top portion of the wall and they were able to ride the wall down, which is quite possibly why they were able to survive. The other two workers were on the interior side on scaffold and they were caught in the collapse," Eugene Corcoran, Deputy Commissioner of Enforcement, said.
Gerado Escalona had just started working at the construction site along Queens Boulevard when he says he saw the wall beginning to give way.
"And then one of the walls collapsed on top of the four guys," he said.
It took firefighters several minutes to free one of the workers.
"He was trapped between the scaffolding and the cinderblock wall, so they had to do some minor cutting of the scaffolding to get that worker out," Deputy Chief Dan Brown said.
The 26-year-old worker was rushed to Elmhurst Hospital where he died from his injuries. The three others suffered serious injuries.
The workers' death is the first of the new year. Last year four workers died on the job. Three were killed in 2009 and 19 were killed in 2008 -- nine of those were in crane accidents.
City buildings officials have now placed a stop work order on the project as several agencies conduct investigations, one focusing on construction procedures used to strengthen the wall.
"It's quite possible there are voids in the wall and the concrete will seep through the voids and the pressure on the exterior will cause the wall to collapse," Corcoran said.
A person at the contractor, H. Rock Co., said no one was available to talk about the workers' death. He said they had no comment.
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