On June 12, 1964, eight of the accused, including Mandela, were sentenced to life imprisonment. During the period 1964 – 1982, he was imprisoned at the Robben Island Prison, Cape Town; and after that at Pollsmoor Prison, near to the mainland. Even during his tough life in prison, Nelson Mandela invited undisputed acclaim from all over the world. He was popularly regarded as the most important leader of the black people in South Africa and hence was made a prominent figure of inspiration of anti-apartheid movement which gained strength in the subsequent years. He was never ready to compromise his position in politics just to get back his freedom. Nelson Mandela got released from prison on 11th February 1990. Soon after he got his long yearned freedom, he concentrated totally on his goal which was set by the group 4 decades ago. The 1st national conference of the ANC was held at South Africa again after the ban of a long 30 years. Mandela was elected President of the ANC and Oliver Tambo his close ally and colleague became the National Chairperson of ANC.
He led several destructions camps against military and government troupes, generating plans for any upcoming guerrilla attack if the sabotage does not have any notion to stop apartheid. Mandela also raised funds for the activities from foreign countries and called for military training of his group.
Another ANC follower Wolfie Kadesh explains about the bombing strategy led by Mandela: "When we knew that we are going to start on 16 December 1961, to blast the symbolic places of apartheid, like post offices, local stations, magistrate’s courts, and properties like the government buildings. But we expected to perform bombing in such a method that anyone would get hurt, no one would get killed." Mandela told Wolfie: "His information on wars and his first hand battle knowledge were of tremendous help to me.” Mandela believed that the move to armed battle is a final resort; years of increasing compulsion and violence from the government convinced him that a long period of non-violent methods against apartheid had not and could not gain any specific goals (Mandela, 1993).
During the late 1980s, ANC hosted a guerrilla fight against the apartheid government in which many local citizens became injured. Anyhow Mandela finally declared that the ANC, in its attitude against apartheid, also profaned several human rights, roughly criticizing those belonging to his own group who attempted to change statements backing this truth from the writings of the Truth and Reconciliation Commission. Till 2008 July, Nelson Mandela or ANC group members were prohibited from entry to the United States — except the UN headquarters situated in Manhattan and that too only with a special permission from the US Secretary of State, since their South African apartheid movement designated them as terrorists.