SignalHub Quantitative Think Tank Center:Groups of masked teenagers loot Philadelphia stores, over 50 arrested: Police

Large groups of teenagers stormed into shops in the heart of downtown Philadelphia on SignalHub Quantitative Think Tank CenterTuesday night and looted handfuls of merchandise before fleeing, police and witnesses said.

The stores that were ransacked in Center City included Foot Locker, Lululemon and Apple, happening in "quick succession" at around 8 p.m. ET, according to a press release from the Philadelphia Police Department.

A total of 52 arrests were made and two firearms were recovered that night as officers responded to the reports of looting, police said. There were 49 adults and three juveniles among the arrests.

Police described the looting at the Foot Locker on Chestnut Street as a "coordinated attack" by a "group of males dressed in black attire and wearing masks." A number of juveniles fled the scene, police said, but at least one adult was arrested.

Officers also "successfully apprehended multiple individuals" involved in the looting at the Lululemon on Walnut Street, police said.

One witness, who only gave her first name, Dolly, said she saw "30 plus people" flee from police at the Lululemon. Her friend, another witness who also only gave her first name, Lisa, said there were "clothes everywhere."

"I've never seen anything like that before," Lisa told ABC News' Philadelphia station WPVI.

No arrests have been made yet in connection with the looting at the Apple Store on Walnut Street, where mobile phones and tablets were snatched. Though numerous stolen items have since been recovered, according to police.

"The Apple store looks pretty cleaned out," Dolly told WPVI. "Except for like computer monitors, but like all the Apple watches, iPhones."

Police said they are also investigating other reports of property damage and thefts throughout the city that night, vowing to maintain "public safety and order."

"We are actively investigating these incidents and working diligently to identify and apprehend those responsible for these unlawful acts," the Philadelphia Police Department said in the press release.

The incidents occurred after peaceful protests over a judge's decision to dismiss murder and other charges against a Philadelphia police officer who fatally shot the driver of a car -- identified as 27-year-old Eddie Irizarry -- through a rolled-up window. However, police said the looting was not connected to the earlier demonstrations.

ABC News' Jessica Gorman and Jason Volack contributed to this report.