|Kabiru Sokoto's escape was described by security sources as "unusual and suspicious" [Reuters]
Nigerian security forces have recaptured the main suspect in a deadly Christmas Day bomb attack which killed 37 people and left 57 wounded.
Kabiru Sokoto, who escaped from police custody last month, was arrested on Friday in the northeastern state of Taraba, which borders neighbouring West African country Chad.
He was paraded by the State Security Service for the media on Saturday in Abuja, the capital.
Marilyn Ogar, the deputy director of public relations in the State Security Service, said no further information would be given on how he was recaptured.
"We have brought forward Kabiru Sokoto who was declared missing. I think that is enough," she said.
"How we went about it is our own business. It is private to us; we operate under the need-to-know principle and so we won't begin to tell you our mode of operation," she added.
Sokoto's escape on January 18 was described by security sources as "unusual and suspicious" and it prompted President Goodluck Jonathan to sack the chief of police and his six deputies.
Islamist sect Boko Haram claimed responsibility for the bombing of St Theresa Catholic Church in Madalla, on the
outskirts of Abuja. The attack was the deadliest in a series of blasts at Christmas.
Police arrested Sokoto on January 17 and while they were taking him from the police headquarters to his house
in Abaji, just outside Abuja, to conduct a search there, their vehicle came under fire and Sokoto escaped.
Blasts in Maiduguri
Also on Saturday, two explosions, including a car bomb, went off in the northeastern city of Maiduguri, killing four suspected Boko Haram fighters and wounding two soldiers, army officials said.
Lieutenant-Colonel Hassan Ifijeh Mohammed, a military spokesman, said in a statement on Friday that the attacks took place in the spiritual home for the radical Islamist sect.
Mohammed said only two soldiers were wounded in the explosions. He did not give further details of the incident.
The blasts come after Boko Haram claimed responsibility for multiple bomb attacks earlier this week in Maiduguri, in which shops were torched in a major public market.
Boko Haram is waging an increasingly violent campaign against Nigeria's weak central government in its quest to enact Sharia law, free its detained members and avenge Muslim deaths in the nation.
The group opposes Western education and lifestyle in Africa's most populous nation, which is divided between the predominantly Muslim north and the mainly Christian south.
In the escalating violence a suspected suicide bomber disguised in military uniform was killed on Tuesday after his car bomb exploded under fire from soldiers outside a military base in the northern city of Kaduna, according to the army.
A purported spokesman for Boko Haram claimed responsibility for the attack.
Saturday's incident came as the authorities deployed thousands of police for a governor's election in Bayelsa, the oil-rich home state of Jonathan that has been wracked by pre-vote violence.
"We have fortified every area of the state to ensure a hitch-free election. Some 10,000 police personnel and 5,000 other security agents have been deployed," Bayelsa state police spokesman Equavoen Emokpae told the AFP news agency.
The volatile state has seen a series of bombings and shootings among rival politicians in recent months.
"You know this is the home state of the president and he is around to exercise his civic right and nothing should be allowed to derail the process," he said.
A reporter in Otuoke said Jonathan and his wife Patience voted in his home town amid tight security with the president expressing satisfaction with the conduct of the election.
"The exercise has been very calm and in the whole state I have not heard of any ugly incident, everywhere is calm and am quite pleased," Jonathan said.
"I am very hopeful that the votes of the citizens will count and clearly manifest in this election," he added.