A man dressed in a UPS uniform and armed with an "assault pistol" opened fire at a United Parcel Service Inc (UPS.N) package sorting hub in San Francisco, killing three people before fatally shooting himself in the head, police said, Reuters reported.
The shooter and the victims were all drivers, said Steve Gaut, head of investor relations at UPS. The man opened fire while the workers were gathered for their daily morning meeting before going out on their routes, he added.
Two other people were shot and have been taken to an area hospital, San Francisco police said. Police have not identified the gunman or the victims.
The incident was not terrorism related but the motive is not known, Assistant Chief Toney Chaplin told a news conference. Police recovered two firearms from the UPS facility, which employs 350 people.
"We are always saddened by the loss of life to gun violence. Any shooting is one shooting too many," San Francisco Mayor Ed Lee said on Twitter.
Gaut said the facility’s employees have been released from work and he believes most have left the building. The company is providing trauma and grief counseling.
Video showed a massive police presence near the facility, with workers being led out and embracing each other on the sidewalk outside.
"Our thoughts and prayers are with all those touched by this incident," UPS said in a statement.
Victims were taken to the Priscilla Chan and Mark Zuckerberg San Francisco General Hospital, spokesman Brent Andrew said. He said he could not say how many patients were taken to the hospital or give their conditions.
In 2014, a man shot and killed two of his supervisors before turning the gun on himself at a UPS distribution center in Birmingham, Alabama. The gunman had recently been fired from the facility.
The deadliest mass shooting in modern U.S. history occurred in June 2016 when a gunman claiming allegiance to the Islamic State militant group killed 49 people at the Pulse nightclub in Orlando, Florida.
The United States has among the most permissive gun rights of any developed country, with the right to "keep and bear arms" enshrined in the Constitution's Second Amendment. Gun control efforts failed after mass shootings at an elementary school in Newtown, Connecticut, in 2012 and the nightclub shooting in Orlando.
The incident in San Francisco came hours after a gunman wielding a rifle opened fire on Republican U.S. lawmakers practicing near Washington for a charity baseball game, wounding senior Republican leader Steve Scalise and several others before being fatally shot by police.