DENVER (CBS4) – Co-workers of a man, who’s body was found in the rubble of a massive fire, said they saw him trying to escape from an upper floor.

(credit: CBS)

The company that was installing insulation in the five-story apartment building in Denver’s Uptown neighborhood says Roberto Flores-Prieto is the construction worker who authorities said had been missing a day later.

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At 4:45 p.m. Thursday, Denver Fire Dept. Capt. Greg Pixley said that the remains of person who had been missing since the fire started were located in the rubble.

Flores-Prieto, 28, was working with foam insulation before the building at 18th and Emerson Street caught fire. Another construction worker was killed. Six people were also hurt in the fire and one person is in critical condition. None of those people have been identified.

Roberto Flores-Prieto (credit: Facebook)

United Insulators, the company Flores-Prieto works for, is now trying to get an emergency visa to fly in his family from Mexico.

More than 50 construction workers were at the site at midday when the smoke and flames shot into the sky. Workers reported first seeing the fire on the third floor. Some jumped from the second and third floors of the building to escape.

Firefighters say the flames produced a tremendous amount of heat because there was nothing to protect the wood in the building from the fire.

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The inferno led to damage in the neighborhood. The inside of one other building was damaged, and roofs of six other buildings were damaged. More than 30 cars were also destroyed at the scene.

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“A friend of ours called us on our cellphones and said … you’ve got to see this fire. So that’s what we did,” Denverite Virginia Smith said. “It’s just amazing that the wind was not high, and it will be interesting to see what started it.”

It could take as long as two weeks to figure out exactly how the fire was sparked.

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United Insulators has set up a GoFundMe account to try to help Flores-Prieto.