(CNN) -- A deputy stopped to help a motorist in Utah on Thursday, and the motorist allegedly shot him dead. Then he wounded two more deputies while running from the law.
That's how Utah County Sheriff Jim Tracy described a high-speed, bullet-riddled rampage that went on for 50 miles across two counties, until officers were able to corner a suspect.
They critically wounded him in a shootout -- it was the fourth time the man opened fire while on the run, the sheriff said.
The slain officer was Sgt. Cory Wride, a deputy who had been on the force for 19 years. Tracy knew him well and thought highly of him, he told journalists at a news conference. Wride worked directly under him for three years.
"He was a very helpful person, and that's what he was doing," Tracy said, visibly moved. "He was helping people when he stopped."
The wounded deputies were hospitalized and underwent operations. One is expected to recover; the other is in critical condition in an intensive care unit.
The suspect, whom Tracy declined to name, is also expected to recover. He has a "significant" criminal history, Tracy said.
Wride called in a "motorist assist" when he decided to pull off the road to aid what he thought was a disabled vehicle, Tracy said.
The suspect shot Wride, while he was still in his squad car, with what "appears to be a high-powered rifle," Tracy said.
Then he fled the scene.
When other officers got the news, they took up positions at strategic posts to try to intercept the car on the run.
Tracy fears the suspect may have set up the situation on purpose as a roadside ambush.
"He may have very well parked by the side of the road, hoping that some officer would stop behind him," he said.
After the suspect fled, a deputy called in to say that he was pursuing him. Seconds later, the officer was shot in his vehicle, wounded in the head, Tracy said.
The suspect raced away but later wrecked the car he was driving.
He looked for a vehicle to carjack, approaching multiple people and cars, before finding one. He later crashed it, too, Tracy said.
Along the way, he continued shooting.
When deputies caught up with him, the man fired at them, critically wounding yet another deputy, the sheriff's office said. The officers wounded the suspect in the gunfight and took him into custody.
The sheriff's office plans to obtain a warrant to search the suspect's home to try to establish a motive for the shooting rampage.
Tracy personally the broke news of Sgt. Wride's killing to his family.
"He was a good man," the sheriff said.
Wride leaves behind a wife and five children.
CNN's Suzanne Presto contributed to this report.