Harris County sheriff's deputies believe whoever killed the man may have thought the house was empty.
Deputies said the 20-year-old victim, who was later identified as Francisco Orozco, lived with his brother and sister-in-law in the house on Kingslake Forest Drive.
The sister-in-law had to be taken to the hospital for a health issue via ambulance Wednesday night, so the victim was home alone.
While with his wife in the hospital, the brother told deputies he got a call from Orozco just before 11:30 p.m. Wednesday, who said he thought someone was breaking into the house. The brother told the victim to call 911, deputies said.
"When deputies arrived, the house was secure until they got into the backyard. They saw a window had been broken out in the back," Sgt. Ben Beall said. "So when the brother arrived at the house and made entry into the house, they found that the victim had been shot."
Orozco was found shot to death in a bedroom inside the home.
Neighbors said they heard several gunshots.
"It was so many noises that I just thought it was fireworks," said neighbor Sharon Benjamin.
Detectives are still working to determine if the victim was targeted. They said it doesn't appear anything was stolen from the home.
It is possible the suspect saw the ambulance leave and assumed the house was empty, deputies said.
"I'm a father myself, and I have kids in schools and the outcome of this is very destructive," said neighbor Alan Davenport.
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