A man who snapped photos up the skirt of a teenage girl while she shopped for shoes at a mall was arrested after her aunt spotted him and yelled for help, police said.

The 28-year-old Brentwood man approached the 14-year-old girl in a store on Friday, kneeled next to her and pretended to be interested in a pair of shoes on a bottom shelf while taking pictures up her skirt with his cell phone camera, Suffolk County police said on Monday.

The aunt heard the shutter go off, snatched the phone from his hand and cried out for security guards, who held him, police said.

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"It's pretty shocking," Detective Sgt. John Kempf said. "This is a young girl, and she looks her age."

The arrested man was charged with unlawful surveillance, a felony, and endangering the welfare of a child, a misdemeanor. He could face up to four years in prison if convicted of the felony.

Police were searching the cell phone for other upskirt pictures. They said they believed the man was taking the pictures for fun, not selling them or showing them on the Internet.

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