Umaru Yar Adua, the Nigerian president, has ordered troops to be deployed on the streets of the city to contain the violence.
The riots were sparked after electoral workers failed to publicly post results of local elections held on Thursday.
Homes, churches and mosques were burnt down in the rioting fuelled by rumours that the All Nigerian Peoples Party (ANPP) had lost the elections to the ruling People's Democratic Party (PDP).
The ANPP is considered a predominantly Muslim party, while the PDP is mainly Christian.
The violence is the worst since the May 2007 inauguration of Nigeria’s president, who came to power in a vote that international observers dismissed as not credible.
Few Nigerian elections have been deemed free and fair since independence from Britain in 1960, and military takeovers have periodically interrupted civilian rule.
Jos, the administrative capital of Plateau state, had also been the scene of a week of violence between Christians and Muslims in September 2001, which also left hundreds dead.