Civil rights activist Darcus Howe has died aged 74, his biographer has said.
The writer and presenter campaigned for black rights for more than 50 years, wrote for various publications and is praised for having brought a "radical voice".
His biographer Robin Bunce said Mr Howe died peacefully in his sleep on Saturday, adding that Mr Howe's wife Leila Hassan confirmed the news.
Dr Bunce, a historian at Homerton College at the University of Cambridge, told the Press Association: "On a personal level, Darcus was enormously warm and generous and he loved life.
"It was a real privilege to get to know him."
Dr Bunce, who co-wrote the biography - Renegade: The Life and Times of Darcus Howe - with Paul Field, hailed Mr Howe's "grass roots activism" in the 1970s and 80s.
He added: "I think he's also important in the 80s, 90s and 00s, because he brought a radical voice, a voice for egalitarianism and justice, to the mainstream media."
Darcus Howe's work had a big impact on British cultural history & race relations. His work must never be forgotten... he'll be missed. RIP— Charlene White (@CharleneWhite) April 2, 2017
So sad to learn of death of Darcus Howe, anti-racist campaigner never afraid to challenge police racism & corruption, publisher & writer RIP— Claudia Webbe (@ClaudiaWebbe) April 2, 2017
Mr Howe wrote about his 2007 prostate cancer diagnosis and the treatment that followed in an article for The Guardian in 2009.
He said: "Long live the NHS. The campaign to persuade black men to get tested for prostate cancer starts here."
Mr Howe was born on February 26 1943 in Trinidad, and came to the UK in 1961.
He started his journalism career in and around 1968 at The Hustler, a magazine produced in Notting Hill, according to Dr Bunce.
He was editor for more than a decade at Race Today magazine, and more recently was a columnist for The Voice newspaper.
Formidable #darcushowe may he rest in peace. He was a warrior may we continue his fight for peace and justice.— (((Dawn Butler MP))) (@DawnButlerBrent) April 2, 2017
Sad to hear Darcus Howe has died. He was a courageous campaigner against injustice and for equality and civil liberties over decades.— John McDonnell MP (@johnmcdonnellMP) April 2, 2017
Mr Howe also wrote a regular column for the New Statesman, as well as having a column in the Evening Standard in the 1990s.
The activist, who was a member of the British Black Panthers, also worked in broadcasting, doing work for the BBC and Channel 4.
The Voice newspaper tweeted: "We regret to inform you that respected journalist, activist & former @TheVoiceNews columnist £DarcusHowe has died. May he rest in peace."
MP Diane Abbott tweeted: "So sad to hear that Darcus Howe has passed away. One of the standout activists & public intellectuals of his generation."
MP Helen Hayes tweeted: "Sad to hear of the passing of Darcus Howe, great loss to Brixton & to the cause of equality and human rights RIP."