Three workers for a program that treats veterans for post-traumatic stress disorder in California have been found dead along with the suspect who took them hostage in a day-long standoff at the largest veterans' home in the US, officials say.
The bodies of the four were discovered nearly eight hours after the gunman slipped into an employee going-away party in a building where combat veterans of Iraq and Afghanistan receive treatment, said California Highway Patrol Assistant Chief Chris Childs.
The three female victims were employees of the nonprofit organisation Pathway Home treatment program, which is housed on the campus of the Veterans' Home of California-Yountville.
Napa County Sheriff John Robertson declined to identify the victims and the gunman Friday, saying family members still needed to be notified.
Authorities said they know who the gunman was but did not reveal his identity, nor did they know the motive for the attack at the state-run Veterans' Home of California-Yountville, in Napa Valley.
Childs said investigators had not determined a motive.
"It's far too early to say if they were chosen at random," Childs said.
Yountville is around 85km north of San Francisco.
A sheriff's deputy responding to an emergency call got into a shootout with the gunman, but the officer was not injured.
Highway Patrol Sgt. Robert Nacke said negotiators were unable to make contact with the gunman throughout the day.
Larry Kamer told The Associated Press that his wife, Devereaux Smith, was at a morning staff party and told him by phone that the gunman had entered the room quietly, letting some people leave while taking others hostage.
Smith, a fundraiser for the nonprofit Pathway Home, was still inside the facility's dining hall and was not allowed to leave, he said. The Pathway Home, a privately run program on the grounds of the veterans' home, treats veterans of the Iraq and Afghanistan wars with post-traumatic stress disorder.
Police evacuated the property and closed off nearby roads. An armoured police vehicle, ambulances and several fire trucks were at the facility, which houses about 1000 residents.
A group of about 80 students who were on the home's grounds were safely evacuated after being locked down, the sheriff said.
The state Veterans Affairs department said the home which opened in 1984 is the nation's largest veterans' home, with about 1000 elderly and disabled residents.
Yvette Bennett, a wound-care supply worker who supplies the veterans' centre, was turned back when she tried to deliver what she called urgently needed medical supplies for two patients inside.
Of all the medical institutions she has worked with, "this is the most placid, calm, serene place," she said. Earlier this week, when she last visited, she asked a doctor, "What's your magic here?"
"And then 48 hours later this happens," Bennett said.
