WEST VALLEY CITY — An Amber Alert was issued late Monday after a father failed to return his three children to their legal guardian.

Israel Hernandez, 30, lost custody of his children because he was physically abusive, said West Valley City Police Lt. Dalan Taylor. The court awarded custody to the man's sister, but Hernandez was allowed visitation.

The man picked up his children around 10 a.m. Sunday but did not return them to his sister by 9 p.m. Monday as he usually does, Taylor said. An alert was issued just after 10 p.m.

Police believe the man could be headed toward California or Mexico in either a maroon Chevrolet Corsica or a black Cadillac Escalade.

Hernandez has been described as a 5-foot-5, 155-pound Hispanic male with black hair and brown eyes. He may have a mustache and a goatee, police said.

The three children, ranging in age from 3 to 6, are believed to be in danger of physical abuse.

Xiomara Hernandez-Torres, 3, is a 3-foot, 35-pound girl who was last seen wearing a rose colored shirt, black pants and white shoes.

Alicia Hernandez, 6, is 3-foot-6 and 40 pounds. She has black hair and brown eyes. She was last seen wearing a red and pink shirt and white shorts.

Pablo Hernandez, 4, is 3-foot and 30 pounds, with brown hair and brown eyes. He was last seen wearing a blue shirt with white stripes, blue jeans and white shoes.