CHICAGO (CBS) — A Brighton Park man has been charged with trying to rob an off-duty Chicago police officer in a parking garage in the South Loop.

Police said the officer was about to get into his car in a parking garage near Balbo Drive and Wabash Avenue shortly after 7 p.m. on Thursday.

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A man tapped the officer on the shoulder and, with his hand in his sweater, demanded the officer’s keys, claiming he had a gun, and threatening to shoot him, police said.

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The officer was able to overpower the robber and detain him until other officers arrived.

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Isaias Saucedo-Ugalde, 21, was arrested and charged with one count of attempted aggravated robbery. He was due to appear in bond court Friday afternoon.