DETROIT – When two Visalia, Calif., police officers swung their cruisers behind a sport utility vehicle that had been carjacked at gunpoint early Sunday, they prepared for a dangerous high-speed chase.

The 2009 Chevrolet Tahoe roared away with officers in pursuit, but shortly after the suspect made a right turn, operators at General Motors Co.'s OnStar service sent a command that electronically disabled the gas pedal and the SUV gradually came to a halt.

The flustered thief got out and ran, but was quickly nabbed after he climbed several fences and fell into a backyard swimming pool, police said.

It was the first time since OnStar began offering the service in the 2009 model year that it was used to end a chase that could otherwise have had dire consequences.

"He wouldn't have pulled over if OnStar hadn't have shut the vehicle down," said Visalia Police Sgt. Steve Phillips. "Generally pursuits end in a collision."

The whole thing began when Jose Ruiz, 33, of nearby Lindsay, Calif., was sitting in his Tahoe in a lighted parking lot about 3 a.m. Sunday while his cousin was talking on a cell phone in the passenger seat. Out of the corner of his eye, Ruiz saw a man walking toward him.

"He already had a gun out," Ruiz said Monday.

The man pointed a sawed-off shotgun at Ruiz and ordered both men to get out of the Tahoe and empty their pockets. Ruiz's cousin at first refused, but Ruiz told him to obey, knowing that OnStar could find the stolen truck with a global positioning system.

"I was afraid he was going to shoot my cousin. My cousin was arguing with him," Ruiz recalled.

The cousin relented and the man sped off in the truck. Ruiz then sprinted for a nearby pay telephone to call police, but ran into a sheriff's deputy on her break who notified Visalia police.

Officers quickly contacted OnStar and got Ruiz's permission to find the vehicle. A half-hour later, police spotted it a few miles away, but as officers made a U-turn to pursue it, the Tahoe sped off at a high speed, Phillips said.

The suspect made a turn, and police dispatchers told the pursuing officers that OnStar was about to disable the Tahoe. It then rolled to a halt, and the robber was quickly captured.

The 21-year-old suspect was jailed and faces preliminary charges of robbery, carjacking, possession of stolen property and resisting arrest.

Visalia Police Chief Colleen Mestas said the new technology kept officers, other motorists and even the suspect out of a dangerous chase.

"Considering the violent crime that this suspect was wanted for, I was just amazed," she said.

Police chases often end in death, many times for the people in the pursued vehicles, according to the National Highway Traffic Safety Administration. Last year, 334 people were killed nationwide in crashes that stemmed from police pursuits, including five police officers, 235 people in the chased vehicles and 77 who were in cars or trucks not involved in the chases.

Ruiz said police returned his Tahoe, cell phone and wallet to him that night. The only thing they didn't get back was some cash taken from his cousin.

The stolen vehicle slowdown feature isn't offered on all GM vehicles yet, but the company hopes to expand it to the entire lineup as models are updated. For 2010, the feature is on 18 models.

Mestas hopes that both technology like OnStar and more police aircraft can minimize the dangers of chases.

"It would be nice to have a day in law enforcement that you didn't have to actively pursue suspects at high speeds," she said.