The son of late Cuban revolutionary leader Fidel Castro, Fidel Castro Diaz-Balart, committed suicide on Thursday after being treated for months for depression, Cuban state-run media reported.
"Diaz-Balart, who had been attended by a group of doctors for several months due to a state of profound depression, committed suicide this morning," the Cubadebate website said.
Diaz-Balart, 68, also known as "Fidelito" because of how much he looked like his father, had initially been hospitalized for depression and then continued treatment outside of hospital, Reuters reports.
He was born in 1949 out of his father's brief marriage to Mirta Diaz-Balart. Through his mother, he was the cousin of some of Castro's most bitter enemies in the Cuban-American exile community: U.S. Representative Mario Diaz-Balart and former U.S. congressman Lincoln Diaz-Balart.
He was also the subject of a dramatic custody dispute. Cuba biographers say his mother took him with her to the United States when he was aged five after announcing she wanted a divorce from Castro, while he was imprisoned for an attack on the Moncada military barracks in Santiago. Castro was able to bring Fidelito back to Cuba after the 1959 revolution.
A nuclear physicist who studied in the former Soviet Union, he had been working as a scientific counselor to the Cuban Council of State and Vice-president of the Cuban Academy of Sciences at the time of his death.
Previously, from 1980 to 1992, he was head of Cuba's national nuclear program, and spearheaded the development of a nuclear plant on the Caribbean's largest island.
Cuba halted those plans in 1992 because of a lack of funding after the collapse of Cuba's trade and aid ties with the ex-Soviet bloc and Castro Diaz-Balart largely disappeared from public view.
His father, who led the building of a socialist state on the doorstep of the United States during the Cold War, died just over a year ago, on Nov. 26, 2016, aged 90.