The mall was full of shoppers, and people dining in restaurants when the chaos erupted -- and not everyone knew why they were being told to get down.
Bryan Parras was having a beer at the Daily Grill in The Galleria around 9:30pm Thursday.
"Actually playing on my phone, and I noticed folks begin to king of just gesture and what's going on, what's going on?" Parras recalled.
His mother grabbed his arm and told him to get down, and he saw many more people doing the same.
"Some are getting on the floor like flat chested, others are dragging their girlfriends along and their wives. I think I even saw some folks with strollers," Parras said.
A couple of stores down, witnesses saw three masked men enter Ben Bridge Jewelry. The men stole hundreds of thousands of dollars in merchandise, but thousands of people inside the mall didn't know what they were doing.
"At the time, we didn't know whether it was a terrorist, it could have been someone with a bomb, could have been anything," Parras said.
David Anderson, the general manager of The Galleria, released a statement that reads in part:
"Whenever an incident like this occurs in our community, our primary concern is always for the safety of our customers and mall employees. We are pleased to report that no one was injured during this unfortunate incident, and contrary to reports, there were no firearms used in the robbery."
On Friday, shoppers filled the mall, many of them unaware of Thursday night's scare.
"It's kind of spooky because I have small children so we try to stay close together and my nine-year-old has a cell phone," shopper Rachel Thomas said.
"It's one of the bigger malls in Houston, so there has to be more security; I think there has to be more security outside," shopper Astrubal Russo said.
And those who were there describe those few minutes say they weren't sure how it was going to end.
"It was just a heist it seems, there was no threat hopefully to any of the folks shopping, and luckily no one tried to stop them," Parras said.
A spokesperson for Ben Bridge Jewelry says there is video surveillance from the store and police are reviewing it. The store reopened Friday.