An escaped murderer and his son may have hid on the Wind River Indian Reservation, a law enforcement official said Thursday.

"We are going on that assumption," U.S. Deputy Marshal Rex Fullmer said Thursday afternoon, when asked whether Shannon Parazoo was on the Riverton-area reservation.

Parazoo and his son, Alonzo Howard Durgin, escaped Feb. 9 from a work-release program run by the Casper Re-Entry Center.

Authorities searched the Riverton area Wednesday and Thursday, but aren't limiting their focus to the reservation, Fullmer said.

Law enforcement officials have been told through tips that Parazoo and Durgin planned to hide out at the reservation until things cooled down. Fullmer declined to say where the pair may have ultimately planned to go.

Although Parazoo's murder conviction is more than two-decades old, authorities have received information that "leads us to believe that there could be a very violent situation," Fullmer said.

Tipsters have told law enforcement officials that Parazoo and Durgin are looking for guns and intend to use children as human shields if they have to, Fullmer said.

"We consider both to be armed and dangerous at this point," he said.

Parazoo, who is an American Indian, was convicted of second-degree murder in 1985 and sentenced to 20-to-30-years in prison. He also has an attempted escape conviction.

Durgin was convicted of aggravated robbery and aggravated assault in 1997. He robbed a convenience store in Riverton and had a shoot-out with police, Fullmer said.

Authorities believe Parazoo's wife, Rose, and her two children may be with the men. There is no indication they are being held against their will.

Rose Parazoo and her children, ages 12 and 14, haven't been seen since Feb. 9, the day of the walk-out escape, said Natrona County Sheriff's Sgt. Mark Sellers.

She had been living in Natrona County.

The sheriff's department on Monday enlisted the help of the U.S. Marshals Service in the search effort, Sellers revealed Thursday. The Marshals Service is responsible for tracking down federal fugitives, but also works with state and local agencies to find escapees.

The decision to contact the Marshals Service was based on the severity of Parazoo's and Durgin's crimes, he added.

Both fugitives had been inmates at the re-entry center since last year. Parazoo was previously incarcerated at the Wyoming State Penitentiary in Rawlins. Durgin was kept at the Wyoming Honor Conservation Camp in Newcastle.

Parazoo, 43, contacted the re-entry center Feb. 9 to say he was headed to his job at a Casper welding company, but wasn't there when a van from the center went to pick him up the following morning.

Durgin, 28, walked away from the center the evening of Feb. 9. He had a pass that allowed him to be with Rose Parazoo, his step-mother, Sellers said.

Authorities are offering a $1,000 reward for information that leads to the fugitives' arrest. Anyone with information should call 911.

Most fugitives are caught with the help of information from the public, Fullmer said.

In April 1985, Shannon Parazoo pleaded guilty to second-degree murder for the beating death of a Gillette man. Parazoo got in a fight with Ronald Clay Tyler near the Natrona-Converse county line following a night of drinking. Tyler died of hypothermia after being left on a rural road.

Reach Joshua Wolfson at (307) 266-0582 or at josh.wolfson@casperstartribune.net.