About 200 people showed up at a Philadelphia mall on Tuesday in a disturbance planned on the social media app Snapchat, leading led to four arrests, ABC affiliate WPVI reported.
Police say they were called with a report of an extremely large crowd of juveniles causing a disturbance at around 6:45 p.m. at the Philadelphia Mills Mall.
Several dozen people made their way inside to the food court, where things began to escalate, according to police.
"They went to the food court area, and that's when they started running around, yelling and screaming and acting disorderly," Philadelphia Police Chief Inspector Scott Small said.
"They were pelting cops with fountain sodas and all kinds of trash," Anthony Clark, a vendor at the mall, told WPVI.
Police say the gathering was planned on Snapchat, adding that one of the individuals arrested may face felony charges after allegedly attempting to strike a police officer.
Officers were able to quickly disperse the crowd after arriving, and police say there were no injuries and no damage to the mall.
Clark said Tuesday was the second night of mayhem at the mall. "When somebody yelled 'gun' last night and the stampede started in our direction, I'm just glad nobody got hurt."
Authorities told WPVI that officers were already at the mall when the Tuesday disturbance began, because of a similar scene Monday night, and that officers will be stationed at the mall all week.
"So it wouldn't make any sense for these juveniles to return, because they're going to be turned away. They're going to be dispersed immediately," Small told WPVI.
The latest incident in Philadelphia came after more than a dozen similar disturbances in malls in at least nine states on Monday.
Also on Tuesday, the Fox River Mall near Appleton, Wisconsin, was evacuated over a report of a person with a gun that turned out to be a false alarm.
Authorities say no threat was found at the mall after police got a call from a family concerned about a man who might have had a gun heading toward the mall, ABC affiliate WKOW reported.
As a precaution, the mall was shut down, but police say they didn't find the man inside and have no reason to believe he was ever there.