The Richard King Mellon Foundation pledged $1 million Monday to help build a memorial to the 9/11 passengers who died on United Airlines Flight 93 when it crashed in Shanksville, Pa.

The organizers of the Flight 93 National Memorial Campaign say they have collected about $45 million of the $60 million cost for the project, which is being built on the site where the hijacked plane went down on Sept. 11, 2001.

The Pittsburgh-based charitable foundation agreed to match every dollar, up to $1 million, collected from donors outside southwestern Pennsylvania. - John P. Martin