CHICAGO (CBS) — Chicago Police Officer Ella French was killed in the line of duty last month, and 800 miles away in New York on the 20th anniversary of the 9/11 attacks, there was a very moving tribute for the fallen officer.

The solemn sounds of “Amazing Grace” filled the air at the Ladder 10/Engine 10 FDNY firehouse, at 124 Liberty St. in Lower Manhattan across from the World Trade Center site.

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On the roof of the firehouse, a flag was hoisted by the FDNY to honor Officer French.

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The United States Marines joined in the ceremony led by Chicago Police Chaplain the Rev. Dan Brandt.

The flag was folded by the Marines after hanging over One World Trade Center. It will be presented to Officer French’s mother, Elizabeth French.

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Officer French was killed on Aug. 7 during a traffic stop in West Englewood.

CBS 2 Chicago Staff