The Red Cross says post-election violence in northern Nigeria has injured 410 people and displaced some 40,000 others.
The violence appeared to subside Wednesday, after defeated presidential candidate Muhammadu Buhari said he would challenge the election results but urged supporters to be calm.
The unrest began Sunday after election officials said Mr. Buhari, a Muslim, had lost the election to President Goodluck Jonathan, a Christian. Muslim supporters of Mr. Buhari attacked churches, homes, and police stations in northern states, sparking reprisal attacks by Christians.
Witnesses have reported seeing charred bodies on roadways, and both mosques and churches burned to the ground.
Media reports say up to 50 people may have died in the violence, though government officials and aid agencies declined to release casualty figures for fear they would prompt a wave of reprisal attacks.
Independent observers say the voting Saturday was largely free and fair. Mr. Buhari says the outcome was affected by computerized vote rigging, and says his party will challenge the results in court.
None of Nigeria’s opposition parties signed on to the final election results. Officials say Mr. Jonathan received more than 22 million votes in Saturday’s polls, nearly twice the number of Mr. Buhari, who garnered about 12 million votes.
Mr. Jonathan won enough support to avoid a run-off, taking 57 percent of the votes cast.
Nigeria’s population of 140 million — the largest in Africa — is split roughly evenly between Muslims and Christians. Most Muslims live in northern Nigeria, while most Christians live in the south.