The Houston Police Department said the shooting happened at the Tierra Del Sol Apartments on Cook Road at about 6:45 p.m.
When officers arrived, they investigated the complex's laundry room and found three people shot.
Two teenage boys were pronounced dead at the scene, and a third was taken to the hospital, where he died.
Asst. Chief Alvaro Guzman said the two teenagers who died at the scene were inside the laundry room when a group of three people got into a disagreement with them, leading to a shootout.
The third teenager who died at the hospital is believed to have been with the group.
Guzman said everyone involved is believed to be teenagers, and they are searching for two persons of interest. HPD said there is no threat to the public.
Eyewitness News spoke with a man who said he heard gunshots before leaving for church.
"I heard the gunshot. It was so loud. When I heard that one, I thought, 'Oh, what is that? Maybe (because it's) Election Day, it's just some celebration.' I turned off the lights and tried to see what's going on," the man told ABC13.
If you know anything about this case, authorities urge you to contact the Houston Police Department's Homicide Division at (713) 308-3600.
Tipsters must contact Crime Stoppers directly to remain anonymous and to be considered for a cash payment by calling 713-222-TIPS (8477), submitting an online tip, or through the Crime Stoppers mobile app.
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