'Fidelito' dead: Fidel Castro's eldest son, scientist Fidel Castro Díaz–Balart, dies aged 68

The 68-year-old was treated for depression before his death, state media reports

Fidel Castro's son Fidel Angel Castro Diaz-Balart, known also as "Fidelito", is seen attending May Day commemorations at Revolution Square (Reuters)

Fidel Castro’s eldest son "Fidelito" has taken his own life, according to Cuban state media

Fidel Ángel Castro Díaz-Balart, also known as “Fidelito”, had been treated for depression in the lead, official state newspaper Granma reported.

Part of the treatment included hospitalisation.

His father Fidel Castro, a revolutionary turned longserving leader of communist Cuba, died in 2016. Mr Díaz-Balart is believed to be one of several children that Mr Castro fathered with multiple different women.

He was born in 1949 after his mother, Mirta Díaz-Balart, married a young Fidel Castro who was still years away from leading in insurrection that toppled the government of Fulgencio Batista. She was reportedly the only woman that Mr Castro ever married.

Ms Díaz-Balart returned to Cuba over the years to visit her son after having moved to Spain.

Mr Díaz-Balart served for a time as head of Cuba’s nuclear power programme, according toThe Miami Herald. He was fired from that position by Fidel Castro himself, the Daily Beast reported.

“There was no resignation,” Mr Castro reportedly said. “He was fired for incompetence. We don’t have a monarchy here.”

Mr Díaz-Balart had studied nuclear physics in the Soviet Union, a key patron and ally of Cuba after the country's Communist takeover.

More recently he was a scientific advisor to the Council of State and Vice President of the Academy of Sciences of Cuba, Granma said.

The paper said Mr Díaz-Balart’s family would handle funeral arrangements.