Maiduguri, Nigeria - A radical Islamist sect in remote northeastern Nigeria claimed responsibility on Wednesday for co-ordinated bombs that killed at least 16 people hours after President Goodluck Jonathan was sworn in.
A spokesman for Boko Haram, a militant group behind years of attacks around the northeastern city of Maiduguri, told the BBC Hausa service it had planted the bombs which tore through bars in the towns of Bauchi, Zaria and Zuba late on Sunday.
The spokesman, identified by the BBC as Abu Zayd, told the radio station, which broadcasts in northern Nigeria, that the sect did not believe in the Nigerian constitution and repeated a call for sharia (Islamic law) to be more widely imposed.
"We are doing what we are doing to fight injustice. If they stop their satanic ways of doing things and the injustices, we would stop what we are doing," Zayd said.
Boko Haram's membership and ideology are ill-defined and it was not possible to verify Zayd's claim of responsibility.
The Nigerian government and security agencies have made no public comment on who might have been behind the attacks beyond saying that investigations are under way.
Bomb attacks in the north have rapidly replaced militant raids on oil facilities in the southern Niger Delta as the main security threat in Africa's most populous nation.
The style of Sunday's strikes, targeting popular drinking dens, one of them near a military barracks, was similar to bombings in Abuja on New Year's Eve which killed at least 10 people. The perpetrators of that attack have never been caught.
The views of Boko Haram, whose name means "Western education is sinful", are not espoused by most of the country's Muslim population, the largest in sub-Saharan Africa.
It is unclear how many followers the sect has but poverty, unemployment and a lack of education in the far northeast have enabled its leaders to build a cult-like following which is as much violently anti-establishment as fervently religious.
Sect members launched an uprising in 2009, attacking government buildings and leading to days of gun battles with the security forces in which as many as 800 people were killed.