The incident happened at the Macy's, according to witnesses and photos obtained by ABC13.
Houston police said one man with a sledgehammer smashed glass cases inside the store. Then, the three other men stole watches.
The suspects got away.
According to multiple tweets posted in the evening, shoppers inside reported hearing gunshots, while others said they heard glass break.
Police later told ABC13 there were no shots fired in the incident.
An employee who works at the Starbucks near Macy's called 911.
"It's scary. I have two little boys, my wife and then my two co-workers were definitely one of them... she was very, very scared," said Oscar Julight.
Another customer said she was with her mom when the chaos happened.
"She just sounded really scared. But I wasn't that scared, just scared for her," Ava Moore said. "I followed my mom's friend and felt safe with her."
The incident comes in the midst of the final weekend before Christmas.
Police at this time do not have a better description of the suspects or a vehicle. Authorities are working to pull surveillance video.
Memorial City Mall has seen its share of chaotic disturbances in the past.
In August, a man wearing a red-half mask caused a panic when he jumped on a table in the food court and declared he was going to kill himself.
No one has been arrested in that incident, but authorities were searching for a person of interest.
SEE ALSO: Masked suspect incites panic after making threats at Memorial City Mall: HPD
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