Law enforcement from the Napa County, the California Highway Patrol and FBI surrounded the Veterans Home of California in Yountville, which is the largest veterans' residence community in the United States, for nearly eight hours.
Brian Goder, a resident of the home who was locked down in the main dining room since 10:45 a.m., says more than a dozen armed troops have marched into the building where the gunman and hostages are holed up.
Officer John Fransen with the CHP confirmed shots have been fired, and it is believed shots were fired at a deputy. Robert Nacke, also with CHP, told reporters that there have been no reported injuries.
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During a 2 p.m. press conference, the first time authorities formally spoke to media about the situation, Sheriff John Robertson with Napa County said law enforcement knows the identity of the suspect but would not release his name. Police, he said, have tried calling the man's cell phone but he has not answered. Robertson said they do not know what motivated the man to begin shooting or take hostages.
Larry Kamer told ABC7 News that his wife and six other women were attending a going away party for a colleague of when the suspect broke in with a rifle. The gunman, Kamer said, let four of the women go, including his wife, and held three hostage.
The women, Kamer said, work with Pathway Home, a non-profit that provides services to veterans. Kamer is also a volunteer with Pathway and formerly sat on the organization's board of directors.
Hostages held in active shooting situation at Yountville veterans home
Negotiators from three agencies are on scene for when law enforcement is able to contact the suspect.
Robertson confirmed that "many bullets" were fired from both sides but reiterated that they do not know of any injuries to the hostages, suspect or deputies.
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Capt. Chris Childs with the CHP said hostages are Pathway Home employees who work with veterans living at the facility.
A group of 80 students from Justin-Siena High School were at the Lincoln Theatre on the property when the situation began but were not close to the building where the shooter has taken hostages. The students were never in any danger, Robertson said, and were placed on lockdown before being moved off the property by bus.
The situation started around 10:30 a.m. Friday, with the Napa County Sheriff's Department issued an alert to residents warning them to avoid the area. The home has been on lockdown since and those in the area have been asked to shelter in place.
The FBI and the Bureau of Alcohol, Tobacco and Firearms have sent agents from their San Francisco Offices, although they have not received a formal request for support, according to ABC News.
ABC7 News crews at the scene have not heard gunshots but report seeing half a dozen ambulances at the property.
Veteran Paul Russo, who lives at the home, had a visceral reaction when he was told to hide. "Go to your room, put all your furniture by the door and hide like cowards? No," he said. "We're veterans, man. We'll take this guy out in a second... I wouldn't kill him first, I'd shoot him in the leg and try to disarm him."
Amanda Vargas, whose husband is the chief of finance in the home's administrative building, said she's been in touch with her husband and he is safe.
"My prayers go out to the people in the residents building," she told ABC7 News. "I hope they are safe and that this gets resolved quickly."
Brenda Espinoza talked to friends inside the home and said they told her a suspect has not yet been caught.
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Events manager Elizabeth Naylor, who was working about 10 miles north of the veterans' home, said she heard waves of emergency sirens. She said she's lived in Yountville since 1995 and is rattled about a shooting so close to home.
"I don't know the world we live in today, I really don't," she said. "This is a little community and we all know each other. Napa Valley is a wonderful, beautiful place and to know this is in your background, it's unsettling."
The home posted an update on its Facebook page at 11:20 a.m. Friday, noting it has activated its emergency response protocol and are working with law enforcement.
About 1,000 male and female disabled and elderly veterans from World War II and the wars in Korea, Vietnam, Afghanistan and Iraq live at the home, according to its website.
The home is near several popular Napa Valley wineries and restaurants and borders Vintners Golf Club, where golfers have been evacuated from the course.
Residents from the home often golf at the club for free, said Jason Boldt at Vintners. "They are friends and family," he said. "We're hoping that everyone is safe."
Authorities have asked tourists and those visiting wine county stay away from the home and surrounding area.
The state Veterans Affairs department says the home opened in 1884. It offers residential accommodations with recreational, social, and therapeutic activities for independent living, according to the home's website.
The grounds also include the theater, a 9-hole golf course, a baseball stadium, bowling lanes, a swimming pool and a military Base Exchange branch store.
Click here for full coverage on the deadly shooting at the Veterans Home of California in Yountville.
RELATED: Yountville veterans home briefly evacuated as wildfires rage in North Bay
Residents were temporarily evacuated from the facility in October when fires raged through Napa County.
Law enforcement is at the Yountville Veteran’s Home right now following reports of gunfire. The safety of our residents, workers and the community is our top priority.— CalVet (@MyCalVet) March 9, 2018
We have activated our emergency response protocol and are cooperating with law enforcement.
Yountville Vet home dates to 1884. Largest vet home in the USA. Has 1000 aged or disabled vets (both men and women): World War II, Korean War, Vietnam War, Desert Storm, and Operation Enduring Freedom/Operation Iraqi Freedom now live at the home. #abc7now— Wayne Freedman (@WayneFreedman) March 9, 2018
The Associated Press contributed to this report