SAN FRANCISCO (CBS SF) — Two of three workers who fell this morning after scaffolding collapsed at a home in San Francisco’s Twin Peaks neighborhood suffered life-threatening injuries, a fire department spokeswoman said.

San Francisco Police Lt. Mike Caplan told KCBS the homeowner did not have a permit for the job and that it started as a simple roof patch, but grew into a full re-roofing job. The workers injured on the job were not affiliated with any contractor.

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The owner told police he probably should have gotten a permit.

The collapse was reported at 9:35 a.m. at a home in the 1400 block of Clayton Street.

The workers—men ages 20, 50 and 58 — were all taken to San Francisco General Hospital with serious injuries. Two of the men were taken in life-threatening condition, fire spokeswoman Mindy Talmadge said.

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Talmadge said there were various bone fractures, among other injuries reported.

The men were hired by the owner of the building, according to Talmadge, but it was later found out they were not affiliated with any contractor.

The owner told police he probably should have gotten a permit.

The California Division of Occupational Safety and Health sent staff to the site to open an investigation, Cal/OSHA spokesman Greg Siggins said.

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