Groups of masked and hooded teenagers broke into and swarmed shops in Philadelphia’s city centre, grabbing merchandise and fleeing on foot in flash mob-style raids, authorities and witnesses say.

An Apple Store was hit at about 8pm local time on Tuesday (00:00 GMT) and police chased fleeing teenagers who raided the shop, recovering dropped iPhones and a “pile of iPads” at one spot, a police statement said.

More than 100 people who appeared to be teenagers looted a Lululemon store, NBC10 Philadelphia reported, citing a police officer.

Video posted on social media showed mostly masked youths in hoodies running out of Lululemon and police officers grabbing several and tackling them to the sidewalk, the Philadelphia Inquirer reported.

No injuries were immediately reported but CBS Philadelphia said a security guard was assaulted at a Foot Locker outlet.

The Philadelphia Inquirer newspaper reported that more than 20 people were arrested, many of whom were young people, during the theft and vandalism spree on Tuesday night.

According to the Inquirer, the city’s acting police commissioner John Stanford said the young people involved appeared to have coordinated the raids using social media and “a caravan of cars” was moving around locations in the city and breaking into shops.

The raids appeared to have been contained by police by midnight local time, the newspaper added.

The flash mob-style ransacking followed an earlier peaceful protest in the city over a judge’s decision on Tuesday to dismiss murder and other charges against a Philadelphia police officer who shot dead a driver, Eddie Irizarry, through a car window.

Several police commanders said the looting was not connected to earlier demonstrations over the judge’s decision, CBS Philadelphia reported.

“This had nothing to do with the protests,” acting police chief Stanford said, according to the Inquirer.

“What we had tonight was a bunch of criminal opportunists take advantage of a situation and try to destroy our city,” he said.

The shop raids occurred on the same day that US budget retailer Target announced it would close nine stores in four states, including one in New York’s East Harlem neighbourhood, and three in the San Francisco Bay Area, saying that theft and organised retail crime have threatened the safety of its workers and customers. (Al Jazeera)

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