Updated

The Latest on the shooting of an Arizona state trooper (all times local):

11:35 a.m.

An Arizona man who helped a wounded state trooper says he was afraid and confused when he saw three bodies and pulled over on a freeway.

Authorities say another motorist had just shot and killed a man who wounded Trooper Edward Andersson early Thursday on Interstate 10 west of Phoenix.

Brian Schober told The Associated Press on Friday that he didn't think twice about stopping when the motorist flagged him down.

He used Andersson's radio to summon help and tried to aid the trooper.

The wounded men were both on the pavement along with a fatally injured woman who had been ejected from the attacker's vehicle.

Authorities say they have not yet determined a motive for the attack. The names of the others involved have not been released.