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NEPTUNE BEACH, Fla. (CBSMiami) — The Florida teenager who was reported missing earlier this week was taken into custody while trying to enter Canada, authorities in Jacksonville said.

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Florida teen Logan Mott and his grandmother Kristina French. (Source: FDLE via WJAX)

Logan Mott, 15, was reported missing, along with his grandmother, Kristina French, 53, after the two failed to pick up Mott’s father from the airport.

Days later, what is believed to be French’s body was discovered buried in a shallow grave in the backyard of Mott’s Neptune Beach home. The home was found ransacked with the door open and guns missing from the safe when Mott’s father and girlfriend returned, opting to take an Uber ride back home when his son failed to show up.

Investigators said they uncovered evidence of foul play and “possible criminal violence” inside the home, according to the Jacksonville Sheriff’s Office.

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Police are in the process of obtaining an arrest warrant for Mott on auto theft charges and are interviewing him to find out what happened in the home.

Mott was the subject of a missing child alert issued by the Florida Department of Law Enforcement. His mother, Carrie Campbell-Mott, pleaded for his return, telling media outlets he was insulin-dependent and didn’t know whether he had his insulin with him.

Investigators now believe he was in possession of his insulin packs.

Campbell-Mott, who lives in Missouri, told WJAX that Logan’s father, who is her ex-husband and French’s son, last heard from French via text on Tuesday when she confirmed she would pick him up at the airport the following day.

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She also said the last time she spoke to her son was Sunday night, and everything seemed fine.