For decades, two men have managed to elude capture after their escapes from the Utah State Prison.

Since the 1980s, Robert Leon Jackson and Lyndal Dale Ritterbush have been alone on a list of the Utah Department of Corrections' most wanted escapees list. Now, authorities have added the names of convicted killers Danny Gallegos and Juan Diaz-Arevalo after their escape from the Daggett County Jail earlier this week.

Jackson and Ritterbush have never been caught.

If they are still out there, Jackson would be 73, and Ritterbush would be 62. Their files are so old, the Utah Department of Corrections said they pre-date computers.

Deseret Morning News archives say that in 1985, Lyndal Ritterbush — then 40 — and another inmate were assigned to drive to the prison dairy to pick up a delivery. They left the truck near some barns and walked away through nearby fields. The other man was captured, Ritterbush remains at large.

Ritterbush was serving time for incest and attempted aggravated sexual abuse of a child. His possible aliases now include "Dale Ritter." At one time, he was on the FBI's Most Wanted list.

Even less is known about Jackson, who escaped in 1981. He was serving time for a robbery conviction dating back to the 1970s, the Utah Department of Corrections said, when he escaped. Details of the escape are unknown.

"He's still out there," said corrections spokesman Jack Ford.

Jackson has some aliases — "Bob Jackson," "Leon Roberts" — and a few tattoos that might identify the elderly escapee. Prison officials said he has a tattoo on his right arm that says "Lucky" and a tattoo on his left hand that says "Eddie." He also has a scar on his right knee and a scar on his nose.

The Utah Department of Corrections has posted the information on their Most Wanted fugitives on its Web site, Also included on the list is 15 parolees who have absconded.

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