Transcript for Police officer killed in mysterious shooting in Indiana
We turn next to the death of a police officer, the first on a scene of a car crash. Rushing to help the people trapped inside the car when one of them then allegedly shot and killed him. Lieutenant Aaron Allan, a six-year veteran of the force, a husband and a devoted father. Tonight, this question, why did they turn on the officer who was trying to help them survive? Here's ABC's gio Benitez. Reporter: Tonight, a growing mystery and tragedy in a small Indiana town. A 38-year-old police officer trying to help people in a car accident, shot and killed. Suspect is still out and about. Reporter: Southport police lieutenant Aaron Allan responding to this rollover crash Thursday when, police say, one man trapped inside the car started shooting. We need to find out what's going on so nobody else gets hurt. Reporter: Backup officers arriving to chaos. Shooting at the car. Officers trying to defend themselves and arms flailing in the car. Reporter: 28-year-old Jason brown was rushed to the hospital and arrested on suspicious of murder. The car's passenger interviewed and released. Reporter: Lieutenant Allan was a husband and father, named the department's officer of the year in 2015. He was killed doing what he loved. He responded to a crash with urgency to preserve life. Tragically, his was lost. Reporter: And David, we still don't know why the suspect fired at lieutenant Allan or what caused that car accident. But we know that he's the 27th officer shot and killed in the line of duty this year. We turn next to an ABC investigation tonight, that
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