It happened shortly before 9pm Monday at a RadioShack off Interstate 45 and West Road.
Investigators say one of the four suspects kneed an employee in the side while getting money out of the register, and another one assaulted a customer who was inside the store.
The suspects fled the scene after stealing an undisclosed amount of cash and some phones.
The employee and customer were treated on scene.
Detectives say the robbery was caught on surveillance video so they plan to review the footage.
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