INDIO, Calif. (AP) _ A 13-year-old girl with several bullet wounds scrambled up a freeway embankment and flagged down a motorist after being left to die in the desert with her raped and murdered cousin, authorities said Friday.

About 12 hours after the child stumbled to Interstate 10 a few miles east of here and 120 miles southeast of Los Angeles, deputies arrested Marcus Garcia Martinez, 23, of Coachella, Riverside County sheriff's Sgt. Ron Dye said.

The bullet-riddled body of Helen Hernandez, also 13, was found in the desert near the Coachella Canal five miles northeast of Coachella, investigators said. Both girls are from Glendale, Ariz., and were visiting relatives in Coachella.

The surviving girl was listed in satisfactory condition Friday evening at Desert Hospital in Palm Springs, a nursing supervisor said.

The sheriff's department was called about 2:20 a.m. Friday. ''She was conscious and gave them a description of the guy,'' and other information, Dye said.

The man apparently befriended the girls at a Coachella convenience store Thursday and they accepted a ride in his car, investigators said.

Martinez, a construction worker employed by a lumber company, was booked for investigation on charges of murder, attempted murder and two counts of rape, Dye said. He was held at Riverside County Jail in lieu of $250,000 bail.

Deputies, requesting assistance from the U.S. Border Patrol, had trailed the gunman's footprints from the crime scene about six miles south to Thermal, Border Patrol Agent Dave Lindemann said.

Investigators used information from the surviving girl and from the abandoned car they found stuck in sand at the crime scene to locate him, officials said.

Martinez was arrested at his sister's home in nearby Desert Hot Springs around 2:40 p.m., Dye said.