Police Probe Deadly Nigeria Blasts
No one has claimed responsibility for the three explosions, which went off in the city of Bauchi a few hours after the inauguration of President Goodluck Jonathan in the capital, Abuja.
Police on Sunday put the death toll at 10 but other officials say the number is likely higher. At least 25 people were wounded in the blasts.
President Jonathan faces the task of uniting a country plagued by frequent political and sectarian violence.
More than 800 people died in post-election violence after Mr. Jonathan was declared the winner of the April presidential election.
Opposition parties are challenging the election results in court, saying the electoral commission falsified the final results.
Many people in Muslim-majority northern Nigeria believed someone from their region should be the next leader after Mr. Jonathan's predecessor, a Muslim, died in office.
Nigeria's ruling People's Democratic Party has a tradition of rotating its presidential nominations between Muslims from the north and Christians from the south, like Mr. Jonathan. The country of 140 million is split almost evenly between the two religious groups.
Political and economic conflicts sometimes escalate into fighting, most often in the central city of Jos, where thousands have been killed in violence over the past decade