A man dressed in a UPS uniform and armed with an “Assault pistol” opened fire at a United Parcel Service package sorting hub in San Francisco, killing three people before fatally shooting himself in the head, police said.

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 gatd 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.

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.

Video showed a massive police presence near the facility, with workers being led out and embracing each other on the sidewalk outside.

San Francisco