Updated

The former Army infantryman who shot and killed three women before taking his own life at a Northern California treatment program was a decorated veteran and an expert rifleman, but he was also troubled by PTSD.

Albert Wong, 36, served in Afghanistan from April 2011 to March 2012 and was an active member of the Army from May 2010 to August 2013, according to Department of Defense records. Wong was described as an expert marksman.

He was awarded a number of medals including the Army Commendation Medal, the Army Good Conduct Medal and the Afghanistan Campaign Medal with two campaign stars.

VICTIMS KILLED IN CALIFORNIA VETERANS HOME STANDOFF DESCRIBED AS ‘BRAVE WOMEN;’ GUNMAN ID’D

Before Wong opened fire Friday morning inside the Pathway Home, a nonprofit post-traumatic stress disorder at the Veterans Home of California-Yountville, he was a patient at the center.

Wong was expelled from the program by Jennifer Golick, the clinical director and one of the women killed. It was not immediately clear why Wong was kicked out of the program.

A motive for the shooting was not immediately clear.

Wong entered the building Friday morning, slipping into a going-away party for some employees. Authorities said he held the three women hostage and sparked a standoff with police lasting nearly eight hours.

Later that day, authorities discovered the bodies of Golick, Christine Loeber, 48, executive director of the program and Jennifer Gonzales, 29, a clinical psychologist.

POLICE: SUSPECT ‘CONTAINED’ IN APARTMENT COMPLEX AMID STANDOFF THAT LEFT COP DEAD

Wong's rental car was later found nearby. A bomb-sniffing dog alerted authorities to something on the car but the only thing found was a cellphone, authorities said.

Yountville Mayor John Dunbar told reporters Saturday, "We lost three beautiful people yesterday and lost one of our heroes who clearly had demons which resulted in the terrible tragedy we all experienced."

The mayor did not comment more explicitly about Wong, but said he has personal info on the veteran that he would share when it was appropriate.

Dunbar said he would be meeeting with Dr. Vito Imbasciani, the secretary of California's Department of Veterans Affairs, to discuss the future of the program and safety measures.

Imbasiciani told reporters Saturday the association was cooperating and working with law enforcement. He said there are safety measures in place for natural disasters and active shooter situations.

According to The Sacramento Bee, the hostage standoff in Yountville has  prompted a California law enforcement union to repeat its appeal to arm the officers who provide security at state hospitals and veterans' facilities.

The San Francisco Chronicle reported the Pathway Home opened in 2008 helping veterans with post-traumatic stress disorder. The center has treated some 450 people.

Fox News’ Benjamin Brown and The Associated Press contributed to this report.