A female suicide bomber blew herself up at a college in Kontagora, northwestern Nigeria on Wednesday, killing a number of students, just two days after a school assembly was hit by a similar attack.
The bomb exploded as the woman entered an auditorium at the Federal College of Education in the town in Niger State, some 150 miles from the capital Abuja. There were conflicting reports on the death toll on Wednesday afternoon, with some witnesses claiming to have seen at least four bodies; others suggested there had been many casualties.
The militant group Boko Haram has attacked a number of educational facilities in northern Nigeria as part of its bid to establish an Islamic caliphate, though they have not yet commented on Wednesday's bombing.
Andrew Randa, a lecturer at the university, told VICE News: "I heard a huge sound. I thought it was construction work but after about 50 seconds I saw people running. So I came out of my office and realised something had gone wrong.
"I tried to make my way out of the college. On the way out I saw someone lying on the floor and one of the heads was decapitated and another part of the leg was. There was a lot of smoke, a lot of dust, people screaming, there was blood everywhere."
Randa said people at the scene told him they saw a female, wearing a hijab and thought to be between the ages of 18 and 22, enter the main auditorium. Five to 10 seconds later the blast went off.
Other witnesses suggested to the BBC's Hausa service that the bomb may have exploded prematurely as the woman tried to gain entry to the packed hall, possibly preventing further casualties.
Randa said that there is almost an equal ratio of females to males in the college, and that he wouldn't be surprised if Boko Haram claimed responsibility for the attack. The group — whose name roughly translates as "Western education is forbidden" — have been behind a spate of attacks and kidnappings in northern Nigeria.
The lecturer said that there are between 5,000 and 6,000 students attending the college, most of whom are hoping to become educators themselves.
This is the second suicide bomb in a place of education in northern Nigeria in three days. On Monday, at least 48 students were killed in Potiskum, Yobe state.
Randa said that Kantagora is generally a peaceful place. "It's very cosmopolitan. You can find everybody from every part of Nigeria doing business and living and working here.
"We try our best security wise, so this came as a shock. I've spent about 10 years here, I'm a lecturer at the college. This is the first time this has happened.
"There was chaos everywhere. All I was thinking was I need to get my kids, I'm going home."
Nigerian President Goodluck Jonathan vowed to defeat Boko Haram when launching his reelection campaign on Tuesday. The government has been heavily criticized for doing very little to combat the militant group.
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