Reuters - 8/28/13, Ian Simpson and Jeff Mason

U.S. President Barack Obama (C) joins members of the King family and other dignitaries to ring a bell on the steps of the Lincoln Memorial during a ceremony commemorating the 50th anniversary of the More...
Credit: REUTERS/Kevin Lamarque

Obama, the first black U.S. president, spoke to thousands of marchers on Washington's National Mall to commemorate King's landmark address, which came to symbolize the struggle for equality among blacks and whites in America.

A bell rang at 3 p.m. EDT (1900 GMT), 50 years to the minute after King ended his clarion call of the civil rights movement with the words "Let freedom ring."

More: Reuters.com

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