SAN FRANCISCO (CBS SF) — Three UPS employees who were fatally shot by their coworker during a work meeting in San Francisco on Wednesday — before the gunman took his own life — have been officially identified.

San Francisco Office of the Chief Medical Examiner identified the three victims as Wayne Chan, 56, of San Francisco, Michael Lefiti, 46, of Hercules, and Benson Louie, 50, of San Francisco.

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San Francisco police said the gunman, who turned the gun on himself after shooting his coworkers, has been identified as 38-year-old San Francisco resident, Jimmy Lam.

Medical Examiner’s Office is continuing to conduct forensic examinations.

Lam was reportedly wearing a UPS uniform when he began shooting. Officers were able to recover two weapons at the scene.

Police said Lam was arrested for DUI in 2010 and again in 2013.

Assistant Police Chief Toney Chaplin said that in addition to the shooting victims, five others suffered various injuries, most of them occurring during the rush to escape.

The ordeal triggered a shelter-in-place order for residents in the area and shut down surrounding streets for much of the day while police evacuated the facility and conducted a search for any additional survivors or victims.

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Investigators have not yet determined a motive for the shooting and do not know if the employees who were shot were specifically targeted, Chaplin said.

They have interviewed all witnesses and are currently interviewing victim’s families in a search for clues.

“We’re going to have to go back and reconstruct not just the last 24 hours, but if there was something that happened in the weeks and months prior,” Chaplin said.

According to UPS spokesman Steve Gaut, about 350 employees work at the facility, which operates as a package sorting hub and delivery center.

“The company is saddened and deeply concerned about affected employees, family members and the community we share,” Gaut said.

San Francisco Mayor Ed Lee issued a statement, offering “condolences and thoughts for the individuals and families affected by the senseless act of violence.”

“We all know the familiar faces of our local UPS drivers and delivery persons,” Lee said. “Today’s tragedy will be felt in every community served by these committed employees.”

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