The 19-year-old Murray resident died after allegedly being shot by her then-boyfriend, Jessi Vega, who has eluded capture since the November 1998 homicide, said Lt. Paul Jaroscak, a Salt Lake County Sheriff's Office spokesman.

"At this point, it's a matter of locating him and getting him into custody," Jaroscak said.

Vega, now 32, faces a first-degree felony charge of murder. He is believed to use the aliases Jesus Mungia and Arturo "Chivo" Munguia.

Detectives hope their search for the alleged killer will get a boost today with the TV show "America's Most Wanted," which will air a segment on the case at 7 p.m. A piece highlighting the case first aired in 2004, but it didn't provide many fruitful leads, Jaroscak said.

Beristain was found by a pair of hunters, authorities said in 1998.

She died from an apparent gunshot wound. As detectives began the investigation, they recovered 9 mm shell casings and a baseball cap with "Jessi" written on it.

"The investigation went fairly quickly," Jaroscak said.

Near the crime scene, a detective found leaves common to the Salt Lake Valley but not the canyon. Several of the same type of leaves were found in a pickup truck owned by Vega.

Deputies received an arrest warrant for Vega, but after pawning several belongings, the accused murderer fled and his trail has since grown cold, Jaroscak said.

"We can't find him. There are 300 million people in the U.S. and trying to find him isn't easy, especially when that person knows they are wanted," he said.

What it's going to take is a tip from "someone watching a show like 'America's Most Wanted,' " Jaroscak said.

Deputies believe Vega has ties to Chicago, Phoenix, Seattle, Eagle Pass, Texas, and in Mexico.

He is described as 5 feet 5 inches tall, 150 pounds, with silver-capped front teeth. Vega has also worn a mustache and goatee, and has a bullet bandolier tattooed from his left shoulder to his right waist line, a Chicago Bulls tattoo on left shoulder and a star tattooed on his left hand.

Jaroscak said Detective Todd Park will be on hand during today's broadcast to help with any tips on Vega's whereabouts.

Since its launch in February 1988, "America's Most Wanted" has helped capture 955 fugitives nationwide, according to the program's Web site.

ngonzalez@sltrib.com