A Ventura County (CA) Sheriff's sergeant was killed responding to a mass shooting at a popular bar in the Los Angeles suburb of Thousand Oaks Wednesday night. Eleven people were killed. The suspected shooter is also dead.

According to Ventura County Sheriff Geoff Dean, the slain Ventura County SO sergeant and a California Highway Patrol officer arrived on the scene at the Borderline Bar and Grill within three minutes of the call coming in and made entry into the establishment because they “heard shots being fired."

When sheriff's Sgt. Ron Helus got to the front door, he was immediately shot multiple times and mortally wounded, according to Dean. The CHP officer stepped back and secured the premises before pulling Helus out of the line of fire. 

“There are 11 victims. I will not count the suspect as a victim,” Dean said. “And then sergeant Helus. Eleven victims, the suspect makes 12 and Sgt. Helus makes 13.”

Helus had been on the force for 29 years and was looking to retire within the next year, CBS Los Angeles reports.

"Ron was a hard-working, dedicated sheriff's sergeant," Dean said as he fought back tears. "He was totally committed. He gave his all and tonight, as I told his wife, he died a hero because he went in to save lives, to save other people."

The suspected shooter has not been identified. He reportedly threw smoke bombs into the packed bar before opening fire on hundreds of people dancing to country music. Law enforcement recovered a .45 caliber handgun at the scene.

Multiple law enforcement agencies responded to the scene. The FBI is aiding in the investigation.