of communism into central Africa. With Soviet support, 2,000 ANC troops launched a major offensive against South Kasai. The attack was extremely successful, but during the course of the offensive, the ANC became involved in infighting between the Baluba and Bena Lulua ethnic groups. and perpetrated a number of large massacres of Luba civilians. Around 3,000 were killed. The violence of the advance caused an exodus of thousands of Baluba civilians who fled their homes to escape the fighting. The involvement of the Soviet Union alarmed the United States. The American government under Eisenhower, in line with Belgian criticism, had long believed that Lumumba was a communist and that the Congo could be on track to become a strategically placed Soviet client state. In August 1960, Central Intelligence Agency (CIA) agents in the region reported to their agency that "Congo [is] experiencing [a] classic communist ... takeover" and warned that the Congo might follow the same path as Cuba. Political disintegration Central government split and first Mobutu coup Lumumba's appeal for Soviet support split the government and led to mounting pressure from Western countries to remove him from power. In addition, both Tshombe and Kalonji appealed to Kasa-Vubu, whom they believed to be both a moderate and federalist, to move against Lumumba's centralism and resolve the secession issue. Meanwhile, Mobutu took effective control of the army, routing foreign aid and promotions to specific units and officers to secure their allegiance. On 5 September 1960, Kasa-Vubu announced on national radio that he had unilaterally dismissed Lumumba, using the massacres in South Kasai as a pretext and with the promise of American backing. Andrew Cordier, the American UN representative in the Congo, used his position to block communications by Lumumba's faction and to prevent a coordinated MNC-L reaction to the news. Both chambers of Parliament, however, supported Lumumba and denounced Kasa-Vubu's action. Lumumba attempted to dismiss Kasa-Vubu from his position, but could not get support for this, precipitating a constitutional crisis. Ostensibly in order to resolve the deadlock, Joseph-Désiré Mobutu launched a bloodless coup and replaced both Kasa-Vubu and Lumumba with a College of Commissionaires-General (Collège des Commissaires-généraux) consisting of a panel of university graduates, led by Justin Bomboko. Soviet military advisors were ordered to leave. Allegedly, the coup was intended to force the politicians to take a cooling-off period before they could resume control. In practice, however, Mobutu sided with Kasa-Vubu