San Diego police say they are trying to identify a 2-year-old girl whose body was found in a duffel bag carried by a couple headed to Mexico.

Police believe the child was killed in the Los Angeles suburb of Whittier, where the couple lived.

San Diego Lt. Ray Valentin said Thursday that police are trying to identify the child and find her parents.

He says investigators have determined how the girl died but aren't releasing that information.

Authorities say 38-year-old Johnny Lewis Hartley and 43-year-old Mercy Mary Becerra were being held on suspicion of murder and child cruelty.

They were arrested Tuesday when they tried to enter Tijuana at the San Ysidro border crossing. They were initially held by Mexican authorities then turned over to U.S. officials.

The suspects didn't immediately respond to messages sent to them in jail.