EUSTIS, FL — Authorities in Florida say a 21-year-old man strangled his pregnant stepmother and called 911 from a cemetery to confess to killing her.

Police officers found Ian Anselmo in Sue Ellen Anselmo's SUV on March 13. The 39-year-old mother of six was bleeding and unconscious in the driver's seat, a cord wrapped taut around her neck.

Lake County charged Ian Anselmo in the assault of his stepmother, but offered no motive in a probable cause affidavit.

The charges are likely to be upgraded because she later died. His father, John Anselmo, tells the Orlando Sentinel "this whole thing seems so weird."

In the 911 call, authorities say Ian Anselmo mentioned an argument. They offered few other details.

The Anselmos had separated a week before the slaying.