SAN FRANCISCO (KCBS)— Construction workers who were building the Mission Bay apartment complex that caught fire Tuesday were lucky to get out, but can’t believe it’s been destroyed.

From the north side across the creek, the building was a wall of flame with a towering column of black smoke above. The northeast corner collapsed and the fire kept spewing burning embers for blocks, some of which sparked a small fire at the UCSF, Smith Cardiovascular Research Building just south of the main fire.

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Firefighters sprinted and were quickly able to extinguish that secondary fire.

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Chris, a carpenter, who declined to give his last name, has spent the last six months framing the apartments that were under construction, now considered a complete loss. He had just moved on to a new job a few blocks away, but came back to watch all his work go up in flames.

“The job was done. It was built. Other than people doing the sheetrock…,” Chris was interrupted by a falling wall from the fire during conversation.

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He only lost tools in the fire, but was relieved to hear all of his co-workers escaped safely.