US President Barack Obama has called on Americans to carry forward the spirit of the civil rights movement during a visit to Selma in the state of Alabama to commemorate the 50th anniversary of a march that prompted the passage of a law extending voting rights to African American minorities.

Obama, the first black US president, spoke on Saturday before thousands of people gathered at the Edmund Pettus Bridge in Selma, where police and state troopers beat and used tear gas against peaceful marchers who were advocating against racial discrimination at the voting booth in 1965.

Obama said that the event in 1965 proved that "non-violent change is possible", adding that it had also inspired the fight for freedom across the world, including in South Africa to the recent protest in Ukraine.

"If Selma taught us anything, it is that our work is never done," he said, citing that efforts

"The Americans who crossed this bridge, they were not physically imposing, but they gave courage to millions. They held no elected office, but they led a nation."

 

The events of 1965 became known as Bloody Sunday and prompted a follow-up march led by civil rights leader Martin Luther King, Jr.

Obama was joined at the event by first lady Michelle Obama and about 100 members of Congress. Former President George W Bush also attended the event.

John Lewis, a member of the US Congress and activist who was at the original march, said "there's more work to be done" for civil rights.

The marchers sang songs including We Shall Overcome as a crowd of some 40,000 people looked on.

Al Jazeera's Patty Culhane, reporting from Selma, said Obama weighed his remarks between acknowledging the progress made by African Americans since 1965, and highlighting that "they have not come far enough".

During a trip to South Carolina on Friday, Obama also spoke about the significance of the Selma commemoration.

"Selma is not just about commemorating the past. It's about honouring the legends who helped change this country through your actions today, in the here and now," he told a town hall-style meeting.

The anniversary comes at a time of renewed focus on racial disparities in the US, including discrimination among law enforcement against black citizens nationwide.

Obama condemned the Missouri city of Ferguson on Friday for "oppressive and abusive" actions against black residents that were revealed in a Justice Department report accusing police and court officials of racial bias.

Source: Al Jazeera and agencies