Petaluma police detectives, investigating what happened to a 17-year-old Petaluma teen with a gunshot wound to his chest, have evidence the teen may have shot himself.

Petaluma Lt. Matt Stapleton Wednesday said the youth hasn't been cooperating with the investigation and has offered differing versions as to what happened to him, including that the shot could have been self-inflicted.

Stapleton said evidence supports the theory he shot himself.

The investigation began Saturday night when the teen stumbled into his father's Petaluma home, suffering from the wound.

The teen, who hasn't been identified, remained hospitalized as of Tuesday, Stapleton said.

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