SANTA ROSA (CBS SF) — Three construction workers suffered minor injuries when two walls bowed outward collapsing trusses at a Cleveland Avenue project Thursday afternoon, a Santa Rosa Fire Department battalion chief said.

Two of the workers for Merritt Construction were able to free themselves from the fallen lumber and a third was quickly extricated when firefighters arrived, Battalion Chief Mark Basque said.

One worker suffered a head injury, one a lower back injury, and the third suffered leg injuries. The injuries are not life threatening and the workers were treated at Santa Rosa Memorial Hospital, Basque said.

The accident happened around 12:30 p.m. at 2005 Cleveland Ave. where a Habit Burger Grill restaurant was under framing construction, Basque said. Work has been stopped while the Santa Rosa Building Department at Cal-OSHA investigates the incident, Basque said.

Bundled trusses between 25 and 30 feet long and four to five feet tall were placed at intervals on top of the walls before they fell, Basque said.

“Something caused the north and south walls to buckle,” Basque said.

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