At least two people are dead after a shooting at a UPS facility in San Francisco on Wednesday morning, San Francisco Deputy Police Chief Mikail Ali said.
The gunman shot himself, and his condition is unknown, Ali said. Investigators are trying to determine if there are any other casualties.
People in the area are advised to shelter in place until instructed otherwise. Law enforcement is concentrated around the UPS San Francisco Customer Center, a couple of blocks east of Franklin Square.
A woman named Michelle, who did not want to provide her last name, was walking to work across the street from a UPS facility when she saw several UPS employees running down the street. They told her to run because there had been a shooting, she told CNN, explaining she ran about a block with the workers.
"I was confused. They crossed the street and when they got to me, they said, 'Run, there is a shooter,' so I started to run with them," she said. "Several of them said it was a driver they worked with who had a gun and opened fired. I feel terrible for the people hurt and for the UPS team that was there but survived."
Antonio Salic told CNN he was working in a house across from the UPS building when he heard shots fired.
"I was working and suddenly I heard shots and I peeked out the window," he said. "I saw people getting out (of the building), and they were wounded. A lot of people were running."
The construction worker said he also saw people on the roof with their hands up, letting police know they were unarmed.
"Police approached and they were taken to a safe place," he said.
UPS spokesman Kyle Peterson released a statement saying there had been an incident inside the company's San Francisco facility.
"Local law enforcement have control of the facility and are conducting an investigation. The company is cooperating with law enforcement. We cannot provide information as to the identity of persons involved at this time, pending the police investigation," the statement said.
Aerial footage showed police leading dozens of people, many in matching brown work uniforms, out of a building. A tactical vehicle arrived shortly thereafter.
The site of the shooting is the Potrero Hill area, a largely residential neighborhood. The shooting was also not far from a Whole Foods market and the brewery that makes Anchor Steam beer.
Residents have been warned to avoid the area because of heavy law enforcement activity. Authorities say they will hold a briefing soon.
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