Houston police received the call at about 2:30 p.m. Thursday to the Diamond Shamrock gas station near Eastex Freeway and Tidwell Road.
According to Det. Norman Wallace, the victim was walking back to his car at the gas pump when the suspect approached him and said, "Give it up." The suspect then allegedly shot him in the stomach and took off with his car.
HPD does not believe the suspect and victim knew each other.
Lt. Larry Crowson said the victim, who is in his mid-30s, was transported to the hospital, where he underwent surgery but did not survive.
Investigators are currently in the process of interviewing witnesses and going through surveillance video. They are asking for the public's help in looking for a white 2007 Honda Accord with Texas license plate MPT 2517.
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