On September 12, 1977, Stephen Biko, leader of South Africa's Black Consciousness movement, dies shackled on the filthy floor of a police hospital. Earlier that month, he was nearly beaten to death by Afrikaner police in Port Elizabeth for his alleged subversion. News of the political killing, denied by the country's minority white government, led to international protests and a U.N.-imposed arms embargo against South Africa. On September 12, 1978, the first annual Day of Martyrs was observed by opponents of apartheid around the world to remember those who gave their lives in the struggle. Apartheid finally ended in South Africa in 1991.