Miguel Mateos-Martinez

A man wanted for killing a Salt Lake City salon owner during a robbery has been added to the U.S. Marshals' 15 Most Wanted list.

Miguel Mateos-Martinez, 20, is wanted in the slaying of Faviola Hernandez at her California Avenue hair salon in August 2007. Police said she was shot during a robbery, when she reached in to her purse and lifted a handgun to grab the cash underneath it.

According to a U.S. Marshals wanted poster, Hernandez was shot and killed in the presence of her two young siblings.

"The victim was not resisting, was not fighting and yet was still gunned down. This is an unimaginable act of violence, and we are determined to do everything we can to track down and apprehend this ruthless criminal," said U.S. Marshals Service director John Clark in a statement Friday.

Another suspect in the case was arrested, but Mateos-Martinez remains at large.

Federal authorities said Mateos-Martinez is a Mexican native and a documented gang member with a violent criminal record. He is described as Hispanic, 5-foot-3 inches tall, 225 pounds, with brown eyes and brown hair, which is often shaved bald. Mateos-Martinez has tatoos on his right forearm, left wrist and hand. The tattoo on his left hand is a chain with a cross.

The U.S. Marshals Service is offering a $25,000 reward for information that leads to Mateos-Martinez's arrest. Anyone with information is urged to call 1-800-336-0102.

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