Sindika Dokolo, a businessman from Congo and husband of Angolan billionaire Isabel dos Santos, died in a diving accident in Dubai on Thursday.
Dokolo's family announced his death in a statement posted to his Twitter account.
"The Dokolo family, his wife, children, mother, brother and sisters have the deepest sorrow and immense sadness to announce the passing of Sindika Dokolo, which occurred on October 29, 2020 in Dubai. We thank all who have expressed their sympathy and kindness and who share our grief," the family statement read.
A colleague and friend of Dokolo, Cedric Mala, and two family members said he died while diving. Mr Mala said Dokolo had years of diving experience and always spoke passionately about it.
On Saturday, Dubai Police's Maritime Rescue Unit confirmed Dokolo's death and told The National the businessman was "brought to the surface by Dubai Police diving rescuers".
Ms Dos Santos paid tribute to her late husband on Thursday, posting a photo of her and Dokolo on Instagram with the caption "My love".
Born in the Congolese capital of Kinshasa, Dokolo, 48, was a major art collector and is said to have owned more than 5,000 contemporary African artworks. He was seen as a leader in a movement to return African art and artefacts to museums on the continent.
Dokolo's late father, Augustin, was a wealthy banker who passed his love of art on to Sindika, according to the family’s website.
He married the daughter of Jose Eduardo dos Santos, who ruled Angola for 38 years, in 2002. Soon after, he started an art foundation.
The couple faced corruption charges after Ms Dos Santos' father stepped down in 2017 and his successor, President Joao Lourenco, embarked on an anti-corruption campaign.
They were accused of steering $1 billion in state funds to companies in which they held stakes during her father’s presidency, reported Reuters.
Angolan authorities seized their accounts late last year. Dokolo and Ms dos Santos denied any allegations of wrongdoing, saying the government targeted them for political reasons, reported AFP.
Amid the controversy, African art remained Dokolo’s passion.
“African art is our history, our identity, our dignity,” he said in an Instagram post last year.