GRAND PRAIRIE, Texas -- Grand Prairie police said a victim of a fatal crash allegedly attempted to carjack a man who stopped to help early Saturday morning.

Investigators said four people were in a sport utility vehicle when it crashed at about 2:30 a.m. on eastbound Interstate 30 at Northwest 19th Street. Steven Baesa, 19, lost control of the 2003 Ford Expedition, and it overturned at least twice, according to police.

Cab driver Darryl Calhoun stopped to help the crash victims, police said. He saw headlights serving on the freeway right before the SUV flipped over.

"The next thing you know, you see the vehicle, just like a NASCAR -- it looked like a NASCAR scene," he said.

Calhoun said he pulled over to help a stunned 14-year-old passenger who was crawling out of the SUV. The teenager ran over to Calhoun's van while he lit flares to divert traffic, he said.

"I said, 'What are you doing?'" Calhoun said. "And I said it twice, he turned around, pulled out of his pants a pistol right at my face."

The boy ran away when officers showed up, police said.

Officers chased the teen through a neighborhood and caught him, investigators said. He faces aggravated robbery charges.

Nineteen-year-old Jacquelyn Martinez, Baesa's girlfriend, was killed when she was thrown from the SUV and run over by several cars on the interstate.

Police said she was struck by a Ford F-150 pickup truck driver by a Dallas man. She was then struck by as many as three other vehicles whose drivers may not have known what they hit, police said.

The Dallas man, who was later contacted at his home, did not realize he had struck the woman, police said. He will not face charges.

It was the fourth traffic fatality in Grand Prairie this year.

Baesa and another man who was inside the SUV fled the scene, police said.

Investigators said Baesa returned to his Cockrell Hill home later Saturday morning and took his belongings. Detectives said he may be on his way to Mexico.

He is wanted on suspicion of failing to stop and render aid, a third-degree felony.

Calhoun said he stopped to help because a good Samaritan rescued him from a bad crash four years ago. He said he thinks a higher power also helped out with this incident.

"Yeah, and I thank the Lord for my safety again, for the second time," he said.

He said he thought he was going to die.

"(I thought) I'm going to leave my wife and my four kids here as a widow," Calhoun said. "I'm just trying to be a good Samaritan. I'm just trying to help."