PHILADELPHIA (CBS) — Four people were arrested after a large crowd of “disorderly,” juveniles gathered at Philadelphia Mills in Northeast Philadelphia on Tuesday night, according to the Philadelphia Police Department.

The arrests follow a second night of chaos at the Philadelphia-area mall.

On Tuesday night, approximately 200 teens arrived via SEPTA bus and descended onto the mall property, but police say they were ready.

Officers were able to keep the majority of the teens outside of the mall, but roughly 30 individuals did make it inside—leaving some shoppers sheltering inside stores.

“When those 30 individuals got in the food court area they started acting disorderly. They were running around they were shouting, yelling, screaming ,” said Philadelphia Chief Inspector, Scott Small.

It’s similar scenes as to what’s been unfolding at various malls around the country, as an odd string of unruly teen flash mobs take over post-holiday shopping.

In some cases, like in Philadelphia shoppers say they were placed on lockdown.

Small says social media played a role in coordinating the flash mobs.

“These teenagers were able to get on social media, specifically Snapchat and they were able to all meet up at this location,” Small said.

The crowd dispersed around 7:00 p.m. and four juveniles are apprehended as a result of the large gathering.

There were no injuries reported, however police say one of the teens attempted to punch a uniform officer.