In 1947 Dominican exiles, including Juan Bosch, had concentrated in Cuba. With the approval and support of Cuba's government, led by Ramón Grau, an expeditionary force was trained with the intention of invading the Dominican Republic and overthrowing Trujillo. However, international pressure, including from the United States, made the exiles abort the expedition. In turn, when Fulgencio Batista was in power, Trujillo initially supported anti-Batista supporters of Carlos Prío Socarrás in Oriente Province in 1955; however, weapons Trujillo sent were soon inherited by Fidel Castro's insurgents when Prío allied with Castro. After 1956, when Trujillo saw that Castro was gaining ground, he started to support Batista with money, planes, equipment, and men. Trujillo, convinced that Batista would prevail, was very surprised when Batista showed up as a fugitive after he had been ousted. Trujillo kept Batista until August 1959 as a "virtual prisoner." Only after paying US$3-4 million could Batista leave for Portugal, which had granted him a visa.