Sheriff's investigators said the two men in their 20s are brothers.
The shooting happened shortly before 2 a.m. Monday at a townhome in the 15100 block of Ella Boulevard near West Airtex Boulevard, just west of the I-45 North Freeway.
When deputies arrived at the scene, they found both men dead with gunshot wounds.
Investigators said their mother was home during the shooting and was the one who called 911. She was taken to the hospital after an apparent panic attack.
The woman told deputies she heard some kind of disturbance in her son's bedroom. She reportedly broke through the locked door and found both of her sons shot.
Investigators believe the 22-year-old brother shot his 24-year-old brother with autism and then turned the gun on himself. One pistol was found at the scene.
HCSO said deputies have responded to previous calls at the address regarding mental health issues and disturbances involving one of the sons.
"At this point, we don't have a motive. We're still trying to figure that out. But we did know medical history with one of the sons. At this point, that's all we have in terms of what could possibly be the motive. But that hasn't been confirmed yet," Sgt. Sidney Miller said.
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