SAN FRANCISCO (CBSDFW/AP) – At least three people were killed in a shooting at a UPS package delivery facility in San Francisco Wednesday morning, and that the shooter was an employee.

UPS spokesman Steve Gaut said Wednesday that he believed the shooter “turned the gun on himself” but did not have additional information.

READ MORE: North Texas Woman Whose Unborn Child Could Not Be Saved Shares Personal Abortion Story

San Francisco police Sgt. Toney Chaplin says at a news conference that two others were wounded Wednesday. He says that the shooter shot himself, and police have not determined a motive.

READ MORE: Texas Secretary of State’s Office Releases New Information On Audit of 2020 Election

The shooting led to a massive police response and a shelter-in-place warning for the surrounding area.

The building is located in the Potrero Hill, which is about 2 1/2 miles from downtown San Francisco.

MORE NEWS: Armed Woman Dies Following Allen Police Officer-Involved Shooting In Wendy's Parking

Police are advising people to avoid the area.