Zimbabwe's main opposition leader Morgan Tsvangirai has died aged 65, a spokesman for his party said.
Mr Tsvangirai died in South Africa, where he had spent more than a year undergoing treatment for cancer.
The veteran politician was known as one of the most prominent opponents of Robert Mugabe and his regime during their 30 years in charge in Zimbabwe.
The Movement for Democratic Change party's vice president Elias Mudzuri described Mr Tsvangirai on Twitter as "our icon and fighter for democracy".
As you are aware that our MDC T President, Dr Morgan Richard Tsvangirai has not been feeling well for some time, it is sad for me to announce that we have lost our icon and fighter for democracy. Our thoughts and prayers are with the family, the party and the nation at this hour.
— Elias Mudzuri (@EngMudzuri) February 14, 2018
Over the course of his political career, Morgan Tsvangirai was arrested on a number of occasions and in 2007 was reportedly tortured by members of Zimbabwe's special forces.
Mr Tsvangirai was made Mr Mugabe's prime minister between 2009 and 2013 after he saw a surge in support in elections. The office of prime minister was abolished in 2013.
93-year-old Mugabe resigned late last year several days after the army seized power.
The opposition leader's death comes only a few months before the first general election in Zimbabwe since Mugabe was ousted, with voters set to take to the polls in May or June.
Tributes were paid to Mr Tsvangirai across social media this evening, including by his former adviser Alex Tawanda Magaisa.
It’s a dark day. Morgan Tsvangirai lost his brave battle with cancer this evening.
The heart breaks with pain.
It was a rare privilege and an honour to have the confidence of this icon of the democratic struggle. My thoughts are with his family #RIPMorganTsvangirai
— Alex T Magaisa ðŸ‡¿ðŸ‡¼ (@Wamagaisa) February 14, 2018
Go well and rest in power, Morgan Tsvangirai. His steadfast courage and willingness to stand tall against one of the most repressive regimes on the African continent should be applauded. He pushed #Zimbabwe's pro-democracy struggle further than anyone. He will be missed by many.
— Jeffrey Smith (@Smith_JeffreyT) February 14, 2018