NEW YORK (CBSNewYork) — Police have arrested a teenager accused of exposing himself to a young child in a Lower East Side apartment building on Saturday.

The NYPD have arrested suspect Christian Pena, 17, of Manhattan.

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Police said Pena exposed his genitals to a 6-year-old girl standing by the elevator and rubbing himself on her right in front of the girl’s grandmother.

“They screamed at him,” neighbor Kelly Sing said. “They were like, ‘Get away, get away, get away,’ and then he ran.”

Lindsey Ellefson told CBS2’s Esha Ray that she can’t believe it happened just outside her door.

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“Living on the ground floor does come with some extra precaution measures that you need to take, but it’s still shocking to know like how close – like feet away,” Ellefson said.

There’s three doors to get into the building, but the gate is the only one that stays locked. Tenants believe the suspect may have gotten through it with the help of a friendly neighbor.

“People are really casual, so they can just come in and out, so I guess he knew that,” Sing said.

Pena has been charged with sex abuse and wreckless endangerment of a child.

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Pena has been arrested 10 times, including Monday. His last arrest was June 15.