Houston police said a group of people was hanging out at a Shell gas station just after midnight at 647 Greens Road near Imperial Valley Drive when a man approached them and pulled out a pistol.
That's when someone in the group pulled out his own gun and fired at the man first, HPD said.
The shooter told investigators the man was wearing a ski mask when he approached him aggressively, attempting to rob him. When the robbery suspect reached for the shooter's waistband, he pulled out his weapon and shot the suspect multiple times, according to HPD.
The man who was shot was taken to the hospital by other people who were with him, police said. He was pronounced dead at the hospital.
Investigators said the shooter fled the scene and called police. He later returned to the scene and spoke to detectives.
Police said the case will be referred to a Harris County Grand Jury for review, which will determine if charges will be filed.