LAKEWOOD, Colo. (CBS4) – OSHA has been called in to investigate a deadly construction accident in Lakewood.

A man ended up buried when a dirt wall suddenly collapsed on him in the Solterra development near C-470 and Alameda. Another worker barely escaped a similar fate.

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A hillside in the backyard of a home had been excavated for a retaining wall. It collapsed on top of the landscape worker.

“He was doing some work toward the bottom of the hillside and part of the hillside sloughed off and collapsed on top of him,” Bruce Kral with West Metro Fire and Rescue said.

His fellow workers tried to free him as quickly as they could dig.

“The workers onsite starting uncovering him immediately, according to their reports he was buried up to his chest,” Kral said.

West Metro Fire and Rescue arrived just a few minutes after the initial 911 call but it was nearly 30 minutes before the worker was unearthed. He was then rushed to a nearby hospital where he later died. The second worker who was also partially trapped was treated at the scene and released.

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Ken Serra owns the home next door.

“My understanding is they were working on the retaining wall back there and that a portion of the wall collapsed,” Serra said.

Serra says the workers are people he sees daily.

“I see them every day. We wave, we nod, we say hello.”

OSHA and the Lakewood Police Department are now investigating the accident.

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The worker who was killed died of a traumatic crushing injury. He was 40 years old. Authorities have not yet released the victim’s name or the name of the company that employed him.