It happened during what police are calling a robbery at a game room on Bissonnet near Fondren around 9:20 p.m. on Monday.
Police say the Houston Fire Department attempted life-saving measures on the guard before he was pronounced dead.
"We don't have any descriptions of the suspect or suspects," Lt. J.P. Horelica said. "If anyone has any information, please call HPD or Crime Stoppers."
Horelica is hopeful that cameras inside the game room will aid in the investigation.
"We should be able to get video of the incident," he said.
The illegal game room is disguised to look like something else on the outside, according to Horelica, who told ABC13 he'd never responded to any calls at the facility before this shooting.
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