Vice President Joe Biden, center, leads a group across the Edmund Pettus Bridge in Selma, Ala., Sunday, March 3, 2013. They were commemorating the 48th anniversary of Bloody Sunday, when police officers beat marchers when they crossed the bridge on a march from Selma to Montgomery. >From left: Selma Mayor George Evans, U.S. Rep. Terri Sewell, D-Ala., Rev. Jesse Jackson, Biden, Rev. Al Sharpton and U.S. Rep. John Lewis, D-Ga. 

Selma, AL-- Vice President Joe Biden told a crowd gathered for the annual commemoration of Bloody Sunday in 1965 that Americans "can't let their guard down" against attempts to restrict access to voting. 

Speaking before the Martin and Coretta King Unity Brunch on Sunday morning, Biden said states had passed 180 laws restricting voting, "some more pernicious than others." 

"Here we are, 48 years after all you did, and we're still fighting?" Biden asked a capacity crowd at Wallace State Community College in Selma. "In 2011, 12 and 13? We're able to beat back most of those attempts in election of 2012, but that doesn't mean it's over." 

The event commemorates "Bloody Sunday," March 7, 1965, when a group of protesters led by current U.S. Rep. John Lewis, D-Ga., were attacked by state and local police as they attempted to cross the Edmund Pettus bridge in Selma. Dr. Martin Luther King, Jr. later led a march from Selma to Montgomery that swelled to 25,000 people by the time it concluded. President Lyndon Johnson signed the Voting Rights Act in August of that year.