Julio Casas Regueiro | Cuban defense chief, 75

Julio Casas Regueiro, 75, a general who oversaw the Cuban military's lucrative economic enterprises for years before replacing Raul Castro as defense minister, died Saturday of heart failure, state television reported.

Gen. Casas was also a vice president of the Council of State, Cuba's supreme governing body. His death was sure to focus renewed attention on the fragility of the island's aging leadership.

State television announced three days of national mourning and immediately began playing retrospective footage of his life. It said that Gen. Casas' body was cremated in accordance with his wishes, and that his remains would be placed in the Defense Ministry headquarters on Havana's Revolution Plaza for public viewing on Monday.

Gen. Casas served under Raul Castro in the rebel army that ultimately pushed out the dictatorship of Fulgencio Batista in early 1959. He was trained as an accountant, a profession that served him well in the Revolutionary Armed Forces, where he ran the military's financial operations for two decades.

"In the past 50 years I don't remember ever criticizing comrade Julio Casas, save that, as we Cubans say, he's very cheap," Raul Castro joked on Feb. 24, 2008, after he was elected to replace his ailing brother Fidel as president.

Among the first things Raul Castro did in the top job was to name Gen. Casas defense minister, the post Cuba's new leader had held for nearly a half-century under his brother. In April, Gen. Casas was also elected a member of the Communist Party's powerful 15-member Politburo.

Under Raul Castro's command in the eastern Sierra Maestra mountains, Gen. Casas fought numerous battles against Batista's troops.

He received additional military training in the Soviet Union and fought in Ethiopia during the years that Cuba sent troops to support African struggles for independence. - AP