Case of Florida Woman Missing With Teen Grandson Takes Grim Turn

Police are searching for a missing teenager and he and his grandmother went missing after his father's home was found ransacked, a CBS affiliate reports.

Logan Mott, 15, and his grandmother, 53-year-old Kristina French, were traveling in a silver four-door Dodge Dart with Florida tags DLLT42, according to a missing child alert that was issued for Logan by the Florida Department of Law Enforcement.

The boy's mother, Carrie Mott, said she last spoke with Logan on Sunday. Then, on Wednesday, Logan and his grandmother were supposed to pick up his dad, Eric Mott, and his girlfriend at the airport. When the two didn't show up, the couple took an Uber back to their Neptune Beach home to find it ransacked. The door was open and guns were missing from a safe.

The couple quickly contacted the Jacksonville Sheriff's Office, and authorities are treating the home as a crime scene.

Police were initially concerned that the teen and his grandmother were both in trouble, as Logan is insulin dependent and doesn't have his insulin pump on him.

The case has taken a turn, however, after police found French's body in a shallow grave behind Eric Mott's home, where Logan also lives.

Officers encountered Logan Friday night and took him into custody "without incident" after an inspection revealed he was the subject of a warrant for grand theft auto out of Florida.

After confirming the warrant with the Neptune Beach Police Department, officers were advised that Logan was also the "person of interest" in French's murder. He hasn't yet been charged in the death of his grandmother.