Round Rock police Chief Allen Banks said during a news conference Wednesday that investigators have not yet determined whether Travis County Sgt. Craig Hutchinson killed himself or whether someone took his gun and used it against him.
Authorities previously said Hutchinson used his police radio around 1:30 a.m. on July 25 to report people prowling behind his house.
Investigators arriving moments later found Hutchinson lying on the ground in his backyard.
Hutchinson was a 32-year veteran officer and was set to retire in September.
Round Rock is about 15 miles from Austin.
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