1971, he matriculated from Mphaphuli High School in Sibasa, Venda where he was elected head of the Student Christian Movement. He subsequently registered to study law at the University of the North (Turfloop) in Limpopo Province in 1972. While at university, Ramaphosa became involved in student politics and joined the South African Students Organisation (SASO) and the Black People's Convention (BPC). This resulted in him being detained in solitary confinement for eleven months in 1974 under Section 6 of the Terrorism Act, 1967, for organising pro-Frelimo rallies. In 1976 he was detained again, following the unrest in Soweto, and held for six months at John Vorster Square under the Terrorism Act. After his release, he became a law clerk for a Johannesburg firm of attorneys and continued with his legal studies through correspondence with the University of South Africa (UNISA), where he obtained his Bachelor of Procurationis degree (B. Proc.) in 1981. Anti-apartheid and labour activism After completing his legal qualifications and obtaining his degree, Ramaphosa joined the Council of Unions of South Africa (CUSA) as an advisor in the legal department. In 1982, CUSA requested that Ramaphosa start a union for mineworkers; this new union was launched in the same year and was named the National Union of Mineworkers (NUM). Ramaphosa was arrested in Lebowa, on the charge of organising or planning to take part in a meeting in Namakgale which had been banned by the local magistrate. In August 1982, CUSA resolved to form the National Union of Mineworkers (NUM), and in December Ramaphosa became its first secretary. Ramaphosa was the conference organiser in the preparations leading to the formation of the Congress of the South African Trade Union (COSATU). He delivered a keynote address at Cosatu's launch rally in Durban in December 1985. In March 1986, he was part of COSATU's delegation which met the African National Congress in Lusaka, Zambia. Ramaphosa was elected as the first general secretary of the union, a position he held until he resigned in June 1991, following his election as secretary-general of the African National Congress (ANC). Under his leadership, union membership grew from 6,000 in 1982 to 300,000 in 1992, giving it control of nearly half of the total black workforce in the South African mining industry. As general secretary, he, James Motlatsi (president of NUM), and Elijah Barayi (vice-president of NUM) also led the mineworkers in one of the