Authorities say an Idaho woman accused of taking her three children in a custody squabble may be in the Phoenix metropolitan area on the way to Mexico.

The FBI in Salt Lake City says an Amber Alert was issued Sunday morning for a 9-year-old boy and two girls, ages 5 and 7.

They say 35-year-old Bertha Sabala Guerrero lost custody of the three children in December after authorities say she left them with a woman she had just met. They were placed in foster care in Caldwell, Idaho.

Authorities say Guerrero picked up the children for a 24-hour visitation Friday and failed to return them the following day. Caldwell police have obtained an arrest warrant for Guerrero for custodial interference.

They say Guerrero has family living in Phoenix and Mexico.