SUNNYVALE (CBS SF) — Three officers of Sunnyvale’s Department of Public Safety will not be charged in the fatal shooting an armed murder suspect nearly two years ago, according to the Santa Clara County District Attorney’s Office.

Detectives Gregory Othon, Christopher Ketchum and Mark Jorgensen were lawful in shooting 53-year-old Glen Griggs on June 5, 2014, according to a 37-page report released Tuesday by the District Attorney’s Office.

At the time of the shooting, Othon had worked 15 years with the department, Ketchum was with the department for six years and Jorgensen had been employed for five years, the report said.

The officers were part of a group serving a warrant for Griggs at his North Fair Oaks Avenue home for the murder of his roommate, Molly Franquemont, who is still missing, according to district attorney’s officials.

The suspect barricaded himself in his room where he was armed with a long gun and threatened the officers, according to the report.

Griggs said he “was not afraid to use” the gun and didn’t follow the detectives’ calls to surrender, the report said.

Additional resources were called for including police K-9 teams, SWAT officers, an armored rescue vehicle and crisis negotiators, according to the report.

Griggs made his way out of his bedroom and moved toward the front entrance, where he faced the officers, the report said.

Another officer used a less-lethal weapon on Griggs, who was temporarily stunned, district attorney’s officials said.

Griggs aimed his weapon at the officers, which led Othon, Ketchum and Jorgensen to fire at him, according to district attorney’s officials.

“Based on this dangerous and volatile situation, the officers were justified in defending themselves and others when they were threatened with bodily injury and death,” Deputy District Attorney Sumerle Davis wrote in the

Paramedics attended to Griggs, who was transported to a hospital and soon after pronounced dead, the report said.

The suspect’s gun appeared to be either a shotgun or rifle, but turned out to be a pellet gun, the report said.

An autopsy performed on Griggs showed he was shot five times and had a “toxic” amount of methamphetamine in his system, according to the report.

Franquemont had moved in with Griggs in January 2013 and was reported missing two months later, the report said.

Before Franquemont disappeared, she told friends that Griggs was “erratic,” talked to himself about torturing other people and she feared he would kill her, according to the report.

Throughout the remainder of 2013, Griggs had multiple contacts with officers claiming he had recently seen Franquemont and was in a relationship with her, the report said.

Griggs was convicted of being an accessory after the fact for the 1980 murder of a 6-year-old boy in Florida, district attorney’s officials said.

Three of Griggs’ girlfriends died while they were in a relationship with him: one had died of natural causes, the second from acute ethanol intoxication and the third woman’s cause of death couldn’t be determined, according to the report.

The suspect had exhibited bizarre, violent and suicidal behavior for years, according to district attorney’s officials.

On one occasion, Griggs made threats to bite officers to transmit AIDS, HIV and Hepatitis C, which he claimed he had, the report said.

In another incident, Griggs set up a booby trap made to burn any officers who went in his room while they served a previous warrant for his arrest, district attorney’s officials said.

Griggs was convicted four other times between 1991 and 2009 of various charges including battery on a peace officer with injury, resisting or obstructing a peace officer, vandalism and DUI, the report said.