Fidel Castro Diaz-Balart, the first son of legendary Cuban leader Fidel Castro, has committed suicide at the age of 68.

Nicknamed Fidelito because of his resemblance to his father, Castro had been receiving treatment for depression for months before he took his life.

“Castro 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,” Cubadebate website said.

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A nuclear physicist who studied in the former Soviet Union, Castro Diaz-Balart 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 programme, and spearheaded the development of a nuclear plant on the Caribbean’s largest island.

Fidelito’s death came just over a year after that of his father on Nov. 25, 2016, aged 90.