This happened when the suspects walked into the store on 5405 South Rice and Westpark Drive around 9 a.m.
Employee Vanessa Coleman was greeting customers when the crooks stormed in. She feared for her life.
"They had masks on and hoodies. It was three guys, three black guys and they just bum-rushed the money center and two went to customer service and grabbed two registers and one grabbed the money center register," said Vanessa Coleman.
She says the suspects put the registers in a cart and took off.
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At the same time employees and customers starting rushing out of the store.
"I got on my radio and I told the people, we being robbed, run and I ran out to the back," said Coleman.
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Officials believe the suspects got away with cash.
"I was in an aisle over here shopping, and I just heard people yelling. At first, I just thought it was kids playing around and then I saw people running and panicking, so I ran out the door," said shopper Julie Ledford.
Multiple police officers could be seen surrounding the store, which has been closed while officials investigate and secure the scene.
Police say they expect the store to reopen soon.
No one was injured.
Officials plan to check surveillance video for more clues about the crime.
If you know who the men are, you're asked to call the Houston Police Department or Crime Stoppers.
Police on the scene at a Walmart in southwest Houston
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