EL RENO, Okla. (AP) — A man charged with murdering his girlfriend and her four young children was in a Texas jail today awaiting extradition to Oklahoma, where investigators had not yet determined the motive for the killings.

The woman had planned to break up with the suspect, her mother said today.

Joshua Steven Durcho, 25, was arrested Tuesday night in Texas’ Hamilton County after his car hit a guard rail and a tree after he had passed a state trooper, said Texas Department of Public Safety spokesman Tom Vinger.

“They passed each other, our trooper is watching him in the rearview mirror, he sees him weaving, and he turns around to investigate. That’s when the suspect’s vehicle crashed,” Vinger said. He said Durcho’s attention might have been focused on the trooper in his rearview mirror instead of the road.

Durcho was treated for minor injuries and was being held without bail at the Hamilton County jail. There was no word if Durcho had an attorney to speak for him.

Prosecutors charged Durcho with five counts of first-degree murder Tuesday, a day after an El Reno police officer conducting a welfare check found Summer Garas, 25, and her children dead in their apartment in the Oklahoma City suburb. The children ranged in age from 3 to 7.

Investigators hadn’t determined a motive for the killings, said Jessica Brown, a spokeswoman for the Oklahoma State Bureau of Investigation.

“We don’t know if it’s a domestic that went terribly wrong,” Brown said. “I know they had their ups and downs in their relationship.”

Garas’ mother, Susan Rust of Carson City, Nev., told The Associated Press today that her daughter had planned to end her relationship with Durcho this past Sunday.

“She said it was over and it was done, and apparently that didn’t go over very well,” Rust said.

“I hope he gets the slowest, most painful death, because that’s what he has earned. Hell is too good for him,” she added.

Besides Garas, daughters Kirsten Rust, 7; Autumn Rust, 6; and Evynn Garas, 3; and son Teagin Rust, 4, were killed. Brown said they weren’t shot, but she didn’t specify how the five were killed.

Susan Rust said the state Medical Examiner had completed autopsies on her daughter and grandson Teagin, and that she was told they were strangled.

According to court records, Durcho was convicted of car theft as a juvenile and was sentenced to four years in prison in 2003 for unlawful possession of marijuana. He was released in February 2007, records show.

“He has been in and out of jail most of his adult life,” Brown said.

Durcho’s page on the MySpace social networking Web site includes pictures of him in a sleeveless shirt, flexing his tattooed arms. He lists interests including tattoos, bodybuilding and the gory “Saw” film series, and warns: “Danger many illegal activities in progress. Enter at your on risk.”

Summer Garas was a student at nearby Redlands Community College, studying to be a legal assistant, school officials confirmed.

“From what I have heard, she was a very intelligent young woman and very well liked by her peers,” college spokeswoman Meg Cannon said. “Obviously, we are going to miss her, and her family is in our thoughts and prayers.”

Court records show that Summer Garas and her ex-husband Jason Garas were divorced on Dec. 10.

Crystal Franklin, Jason Garas’ mother, said Summer Garas rarely locked her door and helped neighbors when they were in need.

“Summer never met an enemy,” she said. “She didn’t have an enemy, just loved everybody.”

Associated Press writers Regina L. Burns and Linda Franklin in Dallas and Sean Murphy in Oklahoma City contributed to this report.