UPPER EAST SIDE, Manhattan— A member of Mayor Bill de Blasio's security detail was shot with a pellet gun outside Gracie Mansion on Sunday, police said.

The female officer was exiting an unmarked police car when she felt pain in her lower back about 7:15p.m.

The officer and her partner immediately investigated and determined the pellets were fired from 170 East End Avenue.

Police say that with help from the building's doorman, they identified the apartment in question and went to the apartment but found nothing.

At around 8:30p.m. the injured officer and her partner saw an 18-year-old male and 17-year-old female exit the building, and took them to the 19th Precinct station house for questioning.

A large team of officers from the Strategic Response Group went to the doorman building across from Gracie Mansion to investigate further.

Their condition is unknown at this time.

Mayor de Blasio is out of town so there is no threat to his security. He has not issued a statement on the shooting.

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