Several clerks were on duty when the masked suspects burst through the doors of the convenience store at the ExxonMobil gas station on 9200 Main and Murworth around 11:30 p.m. Monday.
Se Young Lee was shot during the robbery. He was rushed to the hospital, where he died.
Police released surveillance photos and video of the suspects on Tuesday morning.
One of them is described as a black male wearing a black hoodie with a red "USA" emblem on the front left side of his chest.
The two suspects who went to the counter were also wearing black hoodies. One of those gunmen wore a white skeletal mask.
Even though the victim complied with the suspects' demands, he was still shot multiple times, authorities say.
The cash register was open but it's not clear if any money was taken.
The robbery happened in less than a minute.
"I feel sad. Deeply sad, because I know it's not my company, the gas station, but it could be any of us," said John Villon, who works next door.
Others describe Lee as kind, with one person saying he talked to him every day.
"Energetic, fun. He plays with the kids because I have my grand babies. He plays with my kids and everything. He's a good guy. Just sad this had to happen," said customer Adrian Lacour.
Houston police say they believe these same suspects may be linked to another robbery in the area that happened on Main and Buffalo Speedway about an hour before the deadly incident.
Detectives are still trying to figure out if the suspects had a getaway car or were on foot.
If you have any information about who the suspects are, you're urged to contact Houston Police Homicide at 713-308-3600 or Crime Stoppers at 713-222-8477.
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