US lawmaker John Lewis, a pioneer of the civil rights movement and long-time member of the US House of Representatives, has died, House Speaker Nancy Pelosi said on Saturday.

Lewis, who had announced last year that he had advanced pancreatic cancer, was 80.

Born the son of sharecroppers in 1940 in Alabama, Lewis was one of the original Freedom Riders who fought segregation on the US transportation system in the early 1960s, eventually becoming one of the nation's most powerful voices for justice and equality.

He was also the youngest and last survivor of the Big Six civil rights activists, a group led by the Rev. Martin Luther King Jr. that had the greatest impact on the movement.

He was best known for leading some 600 protesters in the Bloody Sunday march across the Edmund Pettus Bridge in Selma, Alabama.

In 1963, Lewis marched on Washington with King Jr. and, two years later, nearly died from a bloody beating by Alabama state troopers. His campaigning and suffering helped galvanize opposition to racial segregation.

In December, he announced that he had stage-four pancreatic cancer, and pledged to fight it while continuing to serve his constituents in the 5th congressional district of Georgia.

"I have been in some kind of fight — for freedom, equality, basic human rights — for nearly my entire life. I have never faced a fight quite like the one I have now," he wrote in a statement at the time.

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Pelosi leads tributes

"John Lewis was a titan of the civil rights movement whose goodness, faith and bravery transformed our nation — from the determination with which he met discrimination at lunch counters and on Freedom Rides, to the courage he showed as a young man facing down violence and death on Edmund Pettus Bridge, to the moral leadership he brought to the Congress for more than 30 years," Pelosi said in a statement announcing his death.

“In the Congress, John Lewis was revered and beloved on both sides of the aisle and both sides of the Capitol.  All of us were humbled to call Congressman Lewis a colleague, and are heartbroken by his passing."

Tributes poured in from other politicians:

"John Lewis was an icon who fought with every ounce of his being to advance the cause of civil rights for all Americans," said Senator Kamala Harris, the first African American to represent California in the Senate, on Twitter. "I'm devastated for his family, friends, staff - and all those whose lives he touched.

Senator Elizabeth Warren wrote on Twitter, "John Lewis was a true American hero and the moral compass of our nation. May his courage and conviction live on in all of us as we continue to make good trouble for justice and opportunity."

The White House called Lewis a giant of the US civil rights movement.

"Rep. John Lewis was an icon of the civil rights movement, and he leaves an enduring legacy that will never be forgotten," Press Secretary Kayleigh McEnany tweeted.

mm/kp (Reuters, AFP)