A 56-year old ex-con with a violent past is a "person of interest" but not being called a suspect in the case of a missing mother who moonlighted as a professional escort, authorities told FOXNews.com Saturday.

Mesa County Sheriff's spokesperson Heather Gierhart confirmed that Lester Ralph Jones has been named a person of interest in the June 28 disappearance of Paige Birgfeld and that police have searched his home twice, but said she could not confirm "any correlation" between the search of his home and the investigation into Birgfeld's disappearance.

"There are no suspects at all," Gierhart said. "There is a list of people of interest."

Birgfeld's two ex-husbands remain on this list, although authorities "believe their alibis," Giehart said.

She could not confirm that the two search warrants executed at a home Jones shares with his current wife, Elaine Jones, was related to his possible involvement with Birgfeld.

Gierhart said authorities were "not talking about" whether the police have interviewed, or have had any other contact with Jones in relation to the case. Although photographs of Jones—mostly mug shots from previous arrests—have been published in newspapers and on Web sites, the Mesa County Sherrif's office has not released any photographs of him.

Birgfeld, a 34-year old mother of three who led a double life running a professional escort service out of her home, vanished three weeks ago while returning from a visit with her first ex-husband. Birgfeld's family was reportedly unaware of the escort service and believed she ran a home-based business selling Pampered Chef products, according to the Rocky Mountain News. Her ex-husband told police Birgfeld left to keep two appointments with "clients."

Mesa County Sheriff Stan Hikley has said their investigation was focusing on the escort service, Models, Inc. Sources told MyFoxColorado.com that Jones was a client of the escort service.

Lester Ralph Jones, a repairman at an RV company in Grand Junction, has a history of domestic violence. In 1999, Jones reportedly forced his former wife's car off the road, kindapped her at gunpoint, and fired shots at the male passenger in the car, MyFOXColorado.com reported. Jones pleaded guilty to assault with a deadly weapon in the heat of passion and felony menacing, and served five years in prison, according to the Rocky Mountain News.