Associated Press - July 16, 2009 8:55 AM ET

FORT WASHAKIE, Wyo. (AP) - A 20-year-old Ethete (EE'-thu-tee) man has been arrested on suspicion of first-degree murder in a slaying on the Wind River Indian Reservation.

FBI spokeswoman Kathy Wright says Mark James Sonnip is accused of killing 19-year-old Shyrone R. Brown. Brown's body was found in a Fort Washakie home on July 6.

The FBI hasn't said how Brown died, but agents have ruled out gunshots. Wright says final autopsy results are pending. No other details have been released.

The arrest came Friday but wasn't announced until Wednesday.

The FBI has jurisdiction on American Indian reservations. Agents are also investigating the death of 36-year-old Ritchie Tidzump, whose body was found on the Wind River Reservation Saturday with a gunshot wound in the head.

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