It happened at a Sunglass Hut in the King of Prussia Mall around 6:30 p.m. on June 13, the department wrote in a release.
While the employee was taking a phone call, investigators say the three suspects grabbed 23 pairs of sunglasses before walking off. The stolen merchandise is valued at $10,000, according to police.
They left the mall in a silver Nissan Maxima, authorities added.
Suspect one is described as a "heavy-set" man. He was wearing a teal New York Yankees baseball cap, a gray hoodie, and black sweatpants while carrying a brown bag and a white bag, police said.
Suspect two is said to be a "heavy-set" woman wearing a white baseball cap and a white T-shirt while carrying two black shopping bags.
Suspect three is described as a "heavy-set" woman with a long braided ponytail, wearing a grey T-shirt and tan pants with Crocs. She was carrying a Louis Vuitton purse and a large Superdry shopping bag.
Anyone with information is asked to call Upper Merion police at 610-265-3232 or submit an anonymous tip online at the Montgomery County Crime Watch webpage.
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