Tributes are flowing for Zimbabwean musician Oliver "Tuku" Mtukudzi, a star of Afro-jazz who won a following across Africa and beyond after he died on Wednesday aged 66.

According to various local media reports, the self-taught guitarist passed away at a hospital in Harare, succumbing to diabetes complications.

A legend in the vibrant cross-genre music of Afro-jazz, Mtukudzi released 66 albums in a career that spanned 45 years.

He was rated by Forbes magazine as one of Africa's 10 most bankable artists and some experts ranked him alongside Senegal's Salif Keita and Youssou N'Dour for his innovation and influence.

His lyrics, delivered through rasping vocals, often carried social messages about HIV/AIDS and alcohol abuse and encouraging self-respect, sometimes invoking proverbs and wisdom from his mother tongue, Shona.

"Today we said goodbye to a true patriot. Oliver Mtukudzi, your voice has given us comfort during difficult times, and will remain with us for posterity," President Emmerson Mnangagwa wrote on Twitter.

Today we said goodbye to a true patriot. Oliver Mtukudzi, your voice has given us comfort during difficult times, and will remain with us for posterity. Rest in peace comrade. pic.twitter.com/XZkyVbQ4Qq — President of Zimbabwe (@edmnangagwa) January 23, 2019

"If anyone ever made me proud to be Zimbabwean it was you," former Zimbabwean Minister of Education David Coltart said. "Thank you for making us happy for so long, especially during the darkest days".

Rest in peace Oliver Mtukudzi. If anyone ever made me proud to be #Zimbabwean it was you. Thank you for making us happy for so long, especially during the darkest days. pic.twitter.com/K5gsugnb2f — David Coltart (@DavidColtart) January 23, 2019

Former president of South Africa, Jacob Zuma, also paid his respects on Twitter, saying "[Mtukudzi's] music has carried us through some of our darkest and happiest times".

I am deeply saddened by the passing of the legend, Oliver Mtukudzi. His music has carried us through some of our darkest and happiest times, it has also united us across borders. I would like to extend my sincere condolences to his family and friends. Zorora murugare, dear Tuku. pic.twitter.com/gc4pwRQLzB — Jacob G Zuma (@PresJGZuma) January 24, 2019

Mtukudzi's work - dubbed "Tuku music" - was a mixture of ethnic styles, including the Zulu-rooted mbaqanga from South Africa, and drew on diverse instruments, including Zimbabwe's mbira, a metal-tined, hand-held instrument.

We were privileged to share the stage with the great Tuku and had the honour of meeting him in person, said reggae band Morgan Heritage.

"He was a giant of a musician and so humble at the same time. We pray the legacy of this great musician lives on forever".

We were privalidged to share the stage with the great Tuku & have the honor of meeting him in person. He was a giant of a musician & so humble at the same time. We pray the legacy of this great musician lives on forever. Our prayers go out to the family of Oliver Mtukudzi #RIP pic.twitter.com/3zqzGLU9dm — MORGAN HERITAGE (@morganheritage) January 23, 2019

Mtukudzi was famed for his philanthropy and commitment to human rights and served as a goodwill ambassador for the UN's children's agency Unicef.

In an interview with the AFP news agency last March, he played down the acclaim, saying "I don't even understand the word celebrity".

Instead, he said, he set great store by the words of his mother, who declared he would never sing a note better than his first scream after his birth.

"It means when I was born I had already started singing. This is who I am."