A Texas medical examiner says a man whose headless body was found outside a vacant house in Houston died from a gunshot wound to the head.

Police found the head and dismembered body of 35-year-old Marlon Thomas on Sunday evening. They have arrested his best friend, 32-year-old Noe Morin, on a murder charge.

The Harris County medical examiner's spokeswoman, Roxanne Mena, said Tuesday that an autopsy determined Thomas' death was a homicide and he died from the gunshot wound.

Neighbors reported hearing gunshots on Saturday but said the sound wasn't uncommon in the neighborhood. They have described Thomas and Morin as best friends for years and suggested a possible argument over money or theft of property might have led to the slaying.