Five, including officer, killed in fiery Los Angeles standoff

LOS ANGELES, California (CNN) -- A gunman locked in a standoff with Los Angeles police for nearly 12 hours was shot and killed Thursday by officers inside a home, police said.

Four others, including a SWAT officer, died during the ordeal, and another SWAT officer was wounded.

Three of the dead men were discovered inside the home with the gunman. Police said they didn't know how they were related.

Los Angeles police Chief William Bratton said Thursday afternoon that there may have been six people in the Los Angeles-area home -- more than the four that police originally reported -- based on a report from an investigator.

Some of the bodies were badly burned after a fire started at the house toward the end of the standoff, the chief said. A police "flash-bang" device may have started the fire, or the suspect may have set it, Deputy Chief Michael Moore said. Watch the house burn during the standoff »

The incident began about 9 p.m. Wednesday when the suspect called 911 and told police he had killed three family members. Bratton told reporters that the gunman said there were six people in the home.

When officers reached the home in the San Fernando Valley, the man refused to come out. Police said he made no effort to surrender and had no contact with officers, who used loudspeakers and phones in negotiation attempts.

Family members also tried to persuade the gunman to surrender, Moore said, and at one point, a woman was seen outside the house. The woman, he said, witnessed the deaths and was being questioned.

About 5 a.m. Thursday, police used tear gas to try to force out the unidentified gunman.

The nearby AGBU Manoogian-Demirdjian School canceled classes because of clouds of tear gas, spokesman Levon Keshishian said. The private school offers kindergarten through high school.

"We don't want to endanger the students because there is too much tear gas in the area by the school. We're closing it down," he said. The decision was made by the administration, he added. Watch police describe the standoff »

After the gunman died, officers who forced their way into the home discovered two other dead men and one who appeared to be alive, police said. That man was taken outside for treatment by firefighters, then was pronounced dead, Moore said.

The SWAT member was killed just after midnight when police attempted to enter the home for the first time. He was identified as Randal Simmons, 51.

The wounded officer, James Veenstra, also 51, required surgery and was expected to survive, police spokeswoman Karen Smith said. His wife, Michelle Veenstra, is an LAPD captain, sources said. Both men worked with SWAT for 20 years and had many years in the Police Department before that.

"It was a tragedy, but it could have been much worse," Assistant Police Chief Jim McDonald said earlier Thursday.

Mayor Antonio Villaraigosa said he knew Simmons well, because he was assigned to a security detail that watches the mayor's children. Villaraigosa said Simmons was the first Los Angeles SWAT officer to die in the line of duty since the team was established in 1971. E-mail to a friend

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