Houston police were on high alert Sunday as three false shooting incidents were reported in the past 10 days in the fourth largest city in the United States.
Although none of them were attributed to an active shooter in the end, police were on high alert as thousands flocked into shopping malls during Christmas and New Year holiday season.
Police cars were seen parked at the entrances and parking lots of populous malls in Houston, while others patrolled the main streets of the city.
A shooting incident was reported at Memorial City Mall on the evening of Dec. 2, causing hundreds of shoppers to take cover, with some running out through whatever doors they could find.
What people thought was gunfire turned out that a thief with a hammer attempted to break the glass of a jewelry store display case, investigators said.
On Dec. 4, shoppers at a mall in downtown Houston fled when they thought they heard gunshots, which turned out to be noise from a child falling out of a stroller and then tumbling down an escalator.
On Dec. 9, shoppers running frantically from the parking lot of Baybrook Mall said they heard noise like gunshots. But police said after investigation that they could not explain what caused shoppers to run from the parking garage, but there was no evidence of a shooting.
Former FBI agent and security expert Jim Conway told local TV station that people should think about the worst scenario when in a crowded place.
"The best thing to do is err on the side of being safe," he said.
"Paying attention to what's going on around you when you go to a concert or a theater, when you go shopping in a mall, think about where your exits are and where am I going to go if something bad happens," he said.