Updated

NEW YORK -- An anonymous benefactor in New York City stuffed $10,000 in cash into a 9/11 donation box at the World Trade Center.

Joe Daniels, president of the National September 11 Memorial & Museum, tells the New York Post that officials found 99 $100 bills and five 20s in the box on Tuesday night.

The box hangs on a wall at the 9/11 memorial preview site.

Memorial officials believe the money was slipped into the box sometime between 5 p.m. -- when the box was last checked -- and 7 p.m., when the preview site closed.

Officials believe the donation was made by a single person. They say the bills were crisp and unfolded, appearing to have been recently withdrawn from the bank.

Daniels says officials would love to know the donor's name so they could say thank you.