Lagos - Twin car bombings in Jos killed at least 118 people and brought entire buildings down on Tuesday, in the latest affront to the government's internationally-backed security crackdown.
President Goodluck Jonathan swiftly condemned the attack in the central city of Jos, calling it a "tragic assault on human freedom" and condemning the perpetrators as "cruel and evil".
"President Jonathan assures all Nigerians that [the] government remains fully committed to winning the war against terror and... will not be cowed by the atrocities of enemies of human progress and civilisation," his office said.
But the deadly strike and a suicide car bomb attack that killed four in the northern city of Kano on Sunday, will raise fresh questions about the government's grip on the country's security.
Jonathan has already faced calls to quit for failing to ensure the safety of Nigerians and their property as well as come under criticism for his lacklustre response to the kidnapping of more than 200 schoolgirls by Boko Haram militants.
An international team, including specialists from the United States, Britain, France and Israel are involved in the hunt for the 223 teenagers, who were abducted in the remote north-eastern town of Chibok on April 14.
In Jos, the co-ordinator of the National Emergency Management Agency (NEMA), Mohammed Abdulsalam, said buildings collapsed because of the intensity of the blasts in the New Abuja Market area, causing raging fires.
"More bodies may be in the debris," he told AFP, adding: "The exact figure of the dead bodies recovered as at now is 118... 56 people were injured."
The police in Plateau state, of which Jos is the capital, disputed the NEMA figure, however, and maintained that 46 were killed and 45 injured.
"We are saying 46," said state police commissioner Chris Olakpe. "That's the number we have in the morgues. But we are not ruling out more bodies."
The military said improvised explosive devices were hidden in a truck and a minibus. The second went off about 20 minutes after the first, as emergency service workers tended to the victims.
Most of the victims were women, added Pam Ayuba, spokesperson for the state governor, Jonah Jang.
The state and its religiously divided capital have seen deadly sectarian clashes in the past as well as attacks from Boko Haram extremists, who have been waging an increasingly deadly insurgency in the north since 2009.
There was no immediate indication of who was responsible for the latest attacks, although the police in Kano said they had arrested two men in connection with Sunday's bombing, without giving more details.
UN sanctions, emergency rule
The country is under the spotlight as never before over its response to Boko Haram, given the global attention on the plight of the missing girls.
On the day of the mass abduction, the militants launched a car bomb attack on a bus station in a suburb of the capital Abuja which killed 75 and are suspected of a copy-cat attack in the same location on 1 May which left 19 dead.
Nigeria has concentrated on a mainly military response to Boko Haram in the northeast and on Tuesday, parliament approved a further six-month extension to a state of emergency in the states of Borno, Yobe and Adamawa.
Jonathan had requested a continuation of the special powers because of what he said was the "daunting" security situation and mounting civilian casualties.
More than 2 000 people, most of them civilians, have been killed this year alone as a result of the violence and the military's response, according to NEMA, human rights and monitoring groups.
But critics have called into question the military's reliance on conventional tactics to fight an enemy waging a guerrilla war and urged "soft power" strategies to be used at the same time.
Diplomats said on Tuesday that Nigeria had asked a UN Security Council committee that deals with sanctions against al-Qaeda-linked groups to list Boko Haram as a terrorist organisation.
The United States and a number of other countries have already proscribed the militants.
Sporadic attacks in Cameroon, Chad and Niger have meanwhile increased fears of a regional threat and on Saturday, Jonathan and his counterparts from neighbouring countries agreed to boost their co-operation to tackle the problem.
He said "every necessary measure" should be taken to find the still 223 missing schoolgirls, while surrounding countries would contribute a battalion of troops each to patrol the border region and there would be a crackdown on arms trafficking.