The two murderers and a man and a woman awaiting trial for capital murder broke out of the county jail in Montague, about 100 miles northwest of Dallas, on Monday night by overpowering a guard and stealing the guard's car.
"They are considered armed and dangerous. We're looking for them everywhere and the surrounding counties have most of their people on it," a Montague County sheriff's dispatcher said.
Escapees Curtis Gambill and Joshua Bagwell were sentenced to life in prison for the 1996 murder of a 16-year-old Oklahoma cheerleader, Heather Rose Rich, who was killed after a drinking party with the two men. Gambill and Bagwell were in the county jail temporarily because of a court appearance.
The other two who escaped were Crystal Soto, 22, and Charles Jordan, 30, who were charged with capital murder for the deaths in November 2001 of an elderly couple on whose land they were living about 11 miles south of Montague.
"These are some of the most dangerous individuals that exist in our society," District Attorney Tim Cole said. "The two men with life sentences just have absolutely nothing to lose."
Members of the public "need to be very careful," Cole said.
Roadblocks were set up and the FBI joined the search near the Red River along the Texas-Oklahoma line for the fugitives.
Cole said the escapees were believed to be headed to Oklahoma and possibly other states, including Missouri and Oregon. It was not known if they had stayed together or split up.
The sheriff's department said the prisoners used a homemade knife to overpower a female jailer and a female deputy who were on shift around 11 p.m. Monday.
The four then stole the jail guard's sport utility vehicle, a silver Chevrolet Tracker with a black top. The guards were not hurt.
Tuesday morning, at least one discarded black-and-white-striped jail uniform was found under a tree near the jail, said an employee at a nearby bail bond agency.
"I thought, 'Oh my God, those are their clothes.' I was surprised nobody had seen them," Tara Vicari said.
Soto and Jordan were arrested on Nov. 28, in Mason County, Wash., two days after the bodies of James Christmas, 76, and his wife, Ullain, 79, were found in a shallow grave on land they owned near Bowie, 11 miles southeast of Montague.
On Jan. 16, Gambill received a second life prison term after a judge found him guilty of conspiracy to commit murder in the cheerleader killing. Gambill waived his right to a jury trial last summer.
Gambill's first life sentence was handed down in 1997 after he pleaded guilty to killing the cheerleader. Two years after Gambill pleaded guilty to murder, Cole refiled the conspiracy charges, saying Gambill reneged on the plea deal by testifying at Bagwell's trial that another man was the killer.
Bgwell was in the jail as a possible witness against Gambill, but was never called. Bagwell and Gambill were awaiting transfer back to the state prison system, officials said.
© MMII, CBS Worldwide Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press and Reuters Limited contributed to this report