PHOENIX - A Department of Public Safety trooper was shot while responding to a single-vehicle rollover with possible shots fired on westbound interstate 10 near Tonopah on Thursday morning, reports CBS affiliate KPHO.

DPS Capt. Damon Cecil said the trooper, a 27-year-veteran of the agency, was ambushed by the suspect when he got out of his vehicle at the scene of the rollover.

“A physical fight between our trooper and that suspect then ensued, at which time the suspect was shot and killed,” Cecil said. “Right now that’s all we have. This is a fluid investigation.”

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A civilian later got on the trooper’s radio and told DPS dispatchers that the trooper had been shot and that another motorist shot the suspect, the station reports.

“To the civilian on the DPS trooper’s radio, if you can hear me, I need you to let me know where the suspect is that got in an altercation with our trooper,” the dispatcher could be heard saying on the scanner.

“The suspect is uh, occasionally breathing or stirring. He’s been shot by a passer-by,” the man with the wounded trooper’s radio calmly responded. “He’s laying right next to the officer.”

Police have not confirmed how the suspect was shot and killed.

The wounded trooper, who was reportedly shot in the shoulder, was air-lifted from the scene. His injury was reportedly not life-threatening.

The suspect has not been transported, but DPS has not said anything about his condition.

As for the initial rollover, a woman reportedly was ejected from that vehicle. She, like the trooper, was air-lifted from the scene, but her condition was not immediately available.

This is the second shooting involving a law enforcement officer in the Valley so far this year. There were 46 such incidents in the Valley in 2016, plus another 36 in other parts of the state for a total of 82.