The three fatal incidents were among at least six shootings reported overnight.
Colquitt Street
At 7 p.m. on Tuesday, Houston police officers responded to a welfare check at an apartment in the 2000 block of Colquitt Street near McDuffie Street in the Montrose area.
Inside, officers found a man dead. They said it's unclear how he died, but they believe it was not a natural death.
Investigators said neighbors sounded the alarm after not hearing from the man all day.
The medical examiner's office will determine the man's cause of death.
Westpark Drive
About an hour later, officers responded to a shooting at an apartment complex in the 10000 block of Westpark Drive near S. Gessner Road.
At the scene, officers found a 25-year-old woman dead with gunshot wounds.
Investigators believe a man knocked on the woman's door, and when she answered, he forced his way inside and a fight began. It all ended when the woman was shot and killed.
No weapon was found and the suspect is on the run, according to HPD.
Police said there were no witnesses, though neighbors did call police when they heard the man and woman fighting. Investigators were canvassing the area for surveillance video.
Richmond Avenue
The third fatal incident happened around 12:30 a.m. near some food trucks parked at a strip center off Richmond Avenue near Dunvale Road.
Officers found a man dead with gunshot wounds at the scene.
Witnesses in the area reported hearing as many as 15 gunshots.
Investigators said a small crowd of people were gathered, likely getting some food, when the shooting unfolded.
Police believe it may have been a drive-by shooting.
"This area is just, to be honest, it's going in a negative way. My neighbor was killed not too long ago. Since I've been here, I think it's been about five or six times that this has happened," neighbor Jesse Chester said. "It's turning into a normal scene. It's crazy. It just lets me know that I have to leave this area."
Investigators said they believe two suspects were inside a white car, possibly a Honda, when they pulled up to the scene, got out, and started shooting.
Officers were interviewing witnesses. HPD said a person of interest was being questioned.
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