Kano (Nigeria) (AFP) - President Goodluck Jonathan on Monday escaped a suspected suicide bomb blast after he left a campaign rally in northeast Nigeria, as the country braced for fresh Boko Haram attacks before polling day.
The head of state had been addressing supporters of his ruling Peoples Democratic Party (PDP) in Gombe city and had just left the venue when the blast happened in a car park outside.
Rescue workers and health officials said the bodies of two women were brought to the Gombe State Specialist Hospital with 18 people who were injured. The target of the attack was not clear.
"We have evacuated two bodies of females we believe were suicide bombers behind the blast," said the rescue official, who asked to remain anonymous because he was not authorised to speak to media.
Two bombings in the city killed at least five on Sunday, when the Islamists were also repelled from the Borno state capital, Maiduguri, for the second time in a week.
Nigeria's government meanwhile claimed that it had retaken Gamboru and four other towns after a joint weekend offensive by its military, civilian vigilantes and forces from Chad and Cameroon.
"Our troops are in control after operations which had the active support of volunteers (vigilantes) and our friendly neighbours," national security spokesman Mike Omeri told AFP.
The military progress comes after Chadian fighter jets have for three days been bombing Boko Haram positions in the town of Gamboru, according to an AFP reporter in Fotokol, a Cameroonian town less than one kilometre (mile) from Gamboru. The situation appeared quiet by Monday evening, he said.
Security analysts believe the key city of Maiduguri will likely be hit again before polling day, given its symbolism for the group and because it would further undermine the February 14 vote.
The election is expected to be the closest since Nigeria returned to civilian rule in 1999, with the prospect of the PDP being dumped out of power for the first time in 16 years.
- Regional force -
Boko Haram is in control of most of Borno state and has effectively surrounded Maiduguri, which is seen as one of the few places left in the state where voting could feasibly still take place.
But turnout could be affected if large numbers of people, many of them displaced by six years of violence, desert the city, which with other areas in the northeast is a main opposition stronghold.
Capturing Maiduguri would not only be a morale-booster for the rebels but also likely sink Jonathan's re-election bid once and for all, said Obasi.
Chad's offensive comes after the African Union and United Nations last week backed a new 7,500-strong, five-nation force to tackle Boko Haram.
Nigeria's military maintains that N'Djamena's involvement is part of an existing agreement with Chad and Niger for their troops to assist in the counter-insurgency.
Chad and Niger had withdrawn their troops from the multi-national base at Baga, in northern Borno, last year, leaving only Nigerian soldiers to defend the town when it was attacked on January 3, a massive assault in which hundreds were feared killed.
It was that devastating attack that appears to have jolted the multi-national effort back into action.
- Two fronts -
Jonathan, who has been criticised for failing to end the violence, could be hoping for a political bounce from any military successes in the tight election campaign, even at this late stage.
But Mark Schroeder, from security and political analysts Stratfor, believes that allowing foreign forces to operate on Nigerian soil would be counter-productive to him and the country.
"This is essentially absolving Nigeria of its long-standing geopolitical strength as the region's hegemon able to assist internal and pan-West African security stability," he said.
Schroeder, the group's vice-president for Africa analysis, also considered Nigerian army operations no more than "forays", adding that a sustained effort was needed to claw back territory.
Boko Haram's attacks on Maiduguri may be designed to draw the Nigerian army to defend the city, allowing the group to mount strikes elsewhere in the northeast and defend eastern positions.
Ryan Cummings, chief Africa analyst at risk consultants Red24, suggested the last two attacks may have been preliminary tests of the city's defences.
"Boko Haram is currently in its most advantageous tactical position to launch a large-scale offensive on Maiduguri, with the intent of actually capturing the city," he said.
"This could be the preamble to such a push. I still remain sceptical as to whether Boko Haram has the resources to either capture or hold a city the size of Maiduguri.
"But the sect may well be planning to give it a go."
More than 13,000 people have been killed since the beginning of the Boko Haram insurgency in 2009 in Nigeria and close to 1.5 million people have been made homeless.