KANO - A young girl suicide bomber blew herself up and killed five others Sunday in an attack on a market in the northeastern Nigerian city of Potiskum, witnesses and a hospital source said.

Nineteen others who sustained various degrees of injury were taken to hospital after the blast in Potiskum, Yobe state’s commercial capital, a local vigilante leader told AFP. ‘So far, five people were killed with the girl while 19 others have been taken to hospital for injuries,’ Buba Lawan said.

A hospital source speaking on condition of anonymity confirmed the toll of the dead and the wounded. The attack occurred at around 1.30 pm (1230 GMT) during peak hours of business, traders said. Witnesses said she appeared to be as young as seven-years-old and was the latest in a string of child suicide bombers in Nigeria. Previous such attacks have been blamed on Islamist extremist group Boko Haram.

The attack again highlighted the severe security challenges facing Nigeria in the run up to March 28 presidential and parliamentary elections. President Goodluck Jonathan is in a tough re-election bid against ex-military ruler Muhammadu Buhari in the vote, initially scheduled for February 14.

The military pushed for the six-week delay eventually granted by the electoral commission to give it time to secure the country even though the insurgency has raged for six years. Sunday’s incident was the second such suicide attack around the same market, where new and second-hand phones are sold and repaired.

The first attack occurred January 11, when two suicide bombers, one of them appearing to be around 15 years old, blew themselves up outside the market. The attack killed six and injured 37 others.

In Sunday’s attack, suspicious security guards and vigilantes said they had sought to prevent the girl from entering the market.

‘We sent her back four times, because given her age, she did not have anything to do in the market,’ Lawan said. ‘When we were screening people, she bent and tried to pass under the ropes, some distance from our view. That was when the explosives went off.’

In a sign of how much distrust has been generated over the suicide bombings, Lawan said that ‘since the January suicide bomb attacks, we have barred women from entering the market to prevent further attacks.’ Borno, Yobe and Adamawa states, all located in northeastern Nigeria, have witnessed dozens of attacks since Boko Haram intensified its campaign in the region in the past two years. Moreover, Nigerian President Goodluck Jonathan said he underestimated Boko Haram Islamists who have overrun swathes of the country’s northeast and defended an election postponement in an interview published Sunday.

Jonathan, facing a tight re-election bid against ex-military ruler Muhammadu Buhari, has faced criticism over the vote delay, which critics argue was designed to give him time to shore up his campaign. The military pushed for the six-week delay eventually granted by the electoral commission to allow it to secure the country for the vote, though Boko Haram’s insurgency has raged for six years.

Presidential and parliamentary elections are now set for March 28. ‘Probably at the beginning, we, and I mean myself and the team, we underrated the capacity of Boko Haram,’ Jonathan said in an interview with influential newspaper ThisDay. He said that the military has recently acquired more arms and ammunition to do battle with the Islamists, vowing that their suppression and the capture of the group’s leader were near. ‘God willing, we will catch (Abubakar) Shekau before the elections,’ he said.

Asked why six more weeks would make a difference in the years-long conflict that has killed more than 13,000 people, Jonathan said the military could make reasonable progress in that time.

‘We are not saying we must finish Boko Haram to conduct elections, but we should get to a point where they will not cause havoc if they make an attempt,’ he said in the interview.

‘My belief is that by 28th of next month, when the elections will be conducted, Boko Haram may not even be in a position to attack any town, God willing.’ Nigeria’s military authorities on Saturday claimed to have recaptured the fishing town of Baga from the Islamists, more than a month after it was overrun in what is feared to be the worst massacre of the six-year insurgency.

There was no independent corroboration of the claim, as thousands of Baga residents had fled the town after Boko Haram attacked on January 3 and hundreds, if not more, were killed in the following days. Over one million people have been left homeless since 2009 as the rebels try to carve out an Islamic state in northeastern Nigeria. The Islamists have recently extended their violent campaign into nations neighbouring Nigeria’s northeast as regional forces pursue them.