Transcript for Details emerge about Thousand Oaks bar shooting
California and an anguishing new wrinkle in the massacre several weeks at that country music spot. The borderline bar and grill. Investigators now saying the sergeant shot while responding to that attack was actually killed by friendly fire. ABC's Clayton Sandell has the latest from Los Angeles. Good morning, Clayton. Reporter: Good morning, guys. The borderline mass shooting was already an incredible tragedy that just got worse. A friendly fire mishap officials say is devastating and a reminder of the dangers police face every day. When the shooting started at the borderline bar and grill -- He's coming out this door. Reporter: Ventura county sheriff's sergeant Ron helus and a California highway patrol officer both ran into a hellish and chaotic combat zone. Sergeant helus was struck five times by gunfire from the suspect. Both men quickly retreated and fired their rifles at the suspect. Reporter: Sergeant helus might have survived but investigators now reveals he was killed by a shot from the highway patrol's rifle in a case of friendly fire. Whether accidental or mistaken identity is something we're still investigating. This news is extremely difficult for all of us to process and understand. Reporter: It was one month ago that gunman Ian David long threw smoke bombs and opened fire on the crowd including many college students killing 12 people before shooting himself. That fellow officer who shot sergeant helus is a nine-year veteran. I delivered the message. Had no clue it was coming. Surprised Alls of us. He is devastated. He is a consummate professional, well trained, military background. Reporter: Now, investigators want to stress the gunman alone is responsible for what happened and the sheriff tells me when he broke the news to the wife of sergeant helus, she told him she does not blame that officer and she even wants to meet him, whit. Incredible if that meeting were to happen. Clayton Sandell, thanks so much.
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