Sheikh Khalid Abubakar, the imam at the city's main mosque, said more than 300 dead bodies were brought there yesterday alone and 183 were laying near the building waiting to be interred.
It is unlikely that those killed in the Christian community would be taken to the city mosque, raising the possibility that the total death toll could be much higher.
The hostilities mark the worst clashes in the West African nation since 2004, when as many as 700 people died in Plateau State during Christian-Muslim clashes.
Jos, the capital of Plateau State, has a long history of community violence. Rioting in September 2001 killed more than 1,000 people.
The city is in Nigeria's "middle belt," where members of hundreds of ethnic groups live in a band of fertile and hotly contested land separating the Muslim north from the predominantly Christian south.
Authorities imposed an around-the-clock curfew in the hardest-hit areas of the central Nigerian city, where traditionally pastoralist Hausa Muslims live in tense, close quarters with Christians from other ethnic groups.
A statement from the governor of Plateau State, read out on local radio, said the security forces had been directed to shoot on sight to enforce the measure. Sporadic violence had continued overnight despite a previous dawn-to-dusk curfew.
A spokesman for Plateau State governor Jonah Jang said hundreds of weapons had been retrieved at military roadblocks from vehicles trying to enter the city and that the gangs seemed to be getting arms from sympathisers outside the state.
The fighting began as clashes between supporters of the region's two main political parties after the first local election in the town of Jos in more than a decade. But the violence expanded along ethnic and religious fault lines, with Hausas and members of Christian ethnic groups doing battle.
"There is machine-gun fire and there are occasional heavy booms. There is smoke everywhere," said one resident caught up in the unrest. "There are Hausas and (mostly Christian] Beroms who want to fight each other and the army is in the middle trying to create a buffer zone."
Angry mobs gathered on Thursday in Jos after electoral workers failed to publicly post results in ballot collation centres, prompting many onlookers to assume the vote was the latest in a long line of fraudulent Nigerian elections.
Riots flared on Friday morning and at least 15 people were killed. Local ethnic and religious leaders made radio appeals for calm yesterday, and streets were mostly empty by early afternoon. Troops were given orders to shoot rioters on sight.
The violence is the worst since the May 2007, when President Umaru Yar'Adua, came to power in a vote that 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.
More than 10,000 Nigerians have died in sectarian violence since civilian leaders took over from a former military junta in 1999. Political strife over local issues is common in Nigeria, where government offices control massive budgets stemming from the country's oil industry.
Christians and Muslims generally live peacefully side by side in Africa's top oil producer, a country of 140 million people. But hostility has simmered in Plateau State.
The tensions in Plateau State have their roots in decades of resentment by indigenous minority groups, mostly Christian or animist, towards migrants and settlers from Nigeria's Hausa-speaking Muslim north.
Unrest in the state has triggered tit-for-tat killings among different ethnic and religious groups in other areas of the country.