It happened around 1 a.m. in the 3300 block of Dixie Road at Allegheny.
The victim's girlfriend and his sister were inside the business when someone in a red car drove up and opened fire, according to police.
The shooter, described only as a man with a light complexion wearing an olive-colored jacket, took off in the car, Houston police said.
The victim, a 29-year-old man, was shot multiple times and died at the scene. Two others were also shot in the incident and were taken to hospitals, but their conditions weren't immediately known.
"I live about a block and a half from here and been there a couple of months now," one witness said. "About eight shots went off ... pretty much a nightly occurrence really."
The victims' identities weren't immediately known.
Investigators said surveillance video recorded by gas station cameras will give them a good look at the shooter and the vehicle he was in.
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