WEST VALLEY CITY — Investigators had very few clues Wednesday as to the whereabouts of three children police say were taken by their abusive father and his girlfriend.

Xiomara Hernandez-Torres, 3; 4-year-old Pablo Hernandez; and 6-year-old Alicia Hernandez were last seen Sunday night when their father, 30-year-old Israel Hernandez, who has no custodial rights to his children, took them during a scheduled visit. An Amber Alert was issued for the missing children Monday night.

"We're getting a lot of tips, but none of them have grown legs," said West Valley police Capt. Tom McLachlan. "It's getting frustrating for us. Our detectives have been working this thing nonstop, but they're not hitting on anything."

As of Wednesday afternoon, McLachlan said there had been no evidence that Hernandez had used a credit card anywhere, making his footsteps hard to follow.

In 2006, the state gave one of Hernandez's relatives custody of his children because of an ongoing pattern of physical abuse. The abuse resulted in bruises and bleeding and trips to the doctor's office, according to police.

Hernandez is believed to be on the run with his girlfriend, 32-year-old Marta Torres.

Xiomara Hernandez-Torres is 25 pounds and was last seen wearing a rose-colored shirt, black pants and white shoes.

Alicia Hernandez is 3 feet 6 inches tall and weighs 40 pounds. She has black hair and brown eyes and was last seen wearing a red and pink shirt and white shorts.

Pablo Hernandez is 3 feet tall and weighs 30 pounds, with brown hair and brown eyes. He was last seen wearing a blue shirt with white stripes, blue jeans and white shoes.

The group is believed to be traveling in a black Cadillac Escalade or a maroon Chevrolet Corsica. Investigators believe Hernandez, a native of Mexico City, may be headed for the Mexican border.

Anyone with information on Hernandez or the missing children can call 911 or police at 840-4000.

E-mail: preavy@desnews.com