The decision of Zamfara State Governor Ahmad Sani Yerima on 27 October 1999 to adopt the Sharia Penal Code in full — the first Northern state to do so under the Fourth Republic — triggered a cascade across the eleven 'Sharia states' over 2000–2001 (Zamfara, Sokoto, Kano, Katsina, Jigawa, Yobe, Bauchi, Borno, Kebbi, Gombe and Niger). Kaduna State, with a southern Christian population of about 50% and a long history of inter-religious violence, was the most politically combustible candidate.
When the Kaduna State House of Assembly began debate on a Sharia Bill in February 2000, the Christian Association of Nigeria (CAN) Kaduna State chapter organised a peaceful march on 21 February 2000. The march was attacked at Tafawa Balewa Way; the Muslim counter-mobilisation followed; sectarian street fighting then engulfed Kaduna, Kaduna South, Zaria and surrounding districts for five days. A second wave broke on 22 May 2000.
Official federal accounting put the dead between February and May 2000 at 1,000; the Sultan of Sokoto's task team returned 2,000+; the Catholic Diocese of Kaduna returned a body-by-body count of 5,000+; the Red Cross and the Kaduna State Emergency Relief Committee returned an internally displaced count of 200,000. The Sayyaba Plaza commercial district of central Kaduna was destroyed; mosques in Sabon Tasha and Narayi were burnt; churches in Tudun Wada and Rigasa were destroyed; the Polo Club and the Trade Fair Ground served as IDP camps for months.
No prosecutions ever took place. The Kaduna Sharia Bill was withdrawn and replaced with a hybrid 'restricted Sharia' that applied only to consenting Muslims in personal-status matters. The 2000 riots created the permanent residential segregation of Kaduna into a Muslim north and a Christian south along Tafawa Balewa Way and Independence Way — a partition that the Southern Kaduna crisis of 2015– has consolidated. It is the direct precursor of the 2002 Miss World riots, the 2011 post-election violence (800+ dead in Kaduna alone), and the recurrent attacks on Christian villages in southern Kaduna State.