Authorities are still looking for what caused a man to open fire on CHP officers in Riverside on Monday. One CHP officer was killed and two were wounded. The gunman was also killed.

The man identified as the gunman, 49-year-old Aaron Luther, had a lengthy criminal history including serving time in state prison starting in 1994 for attempted second-degree murder and an enhancement for use of a firearm, one count of first-degree burglary and three counts of second-degree burglary, according to the California Department of Corrections and Rehabilitation.

Luther’s wife, McKenzie, told KTLA Luther was battling severe depression. She also expressed her condolences to the family of the fallen officer, 34-year-old Andre Moye Jr.

“I feel really sorry for the other family. This was not characteristic of him. You know, I understand what they’re going through. I’m going through the same thing,” she said.

McKenzie said Luther called her on his way home from work at Malcolm Drilling in Irwindale, where he has worked for the past several years when he was healthy enough.

She said he was totally calm, and told her he had been driving in the carpool lane alone when he was pulled over. She said Luther admitted to the officer that his license was expired and his truck wasn’t insured.

She said Luther told her that he was sure his truck was going to be impounded, and asked her to come to the location so she could collect the tools from his truck.

She said he called her a few times on her way, and asked her to hurry.

She said when she pulled up to the scene with her three young children in the car, bullets were flying. She said she told her kids to get down.

“I saw the cop with the gun, and I was like, ‘oh my God, oh my God, they’re gonna kill him,'” McKenzie said. “I was just screaming at him to stop. Please stop. Just stop. Just stop, baby.”

She said her husband was not supposed to have a gun due to his past criminal history, and doesn’t know why he took it out and started shooting.

“He told me he wasn’t going back to prison. He couldn’t support his family,” she said.

McKenzie said even though he had a criminal past, he was a good father to the eight children and stepchildren that they were raising together.

Correction: An earlier version of this article gave the wrong name for the company where Luther’s wife said he was working in Irwindale. The story has been updated.