It happened at a Valero at Cypresswood Drive and FM 1960.
Deputies said it may have begun as a robbery when a man approached a Jeep in the parking lot. A man in the Jeep was shot, but not before exchanging gunfire with the suspect, authorities said.
The man believed to be the suspect died at the scene. The man in the Jeep was taken to a hospital with what authorities described as non-life threatening injuries.
Investigators are working to get surveillance video from the gas station.
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