Gunmen suspected to be Boko Haram Islamists stormed the northeast Nigerian town of Gajiran on Thursday, opening fire in a market and killing 15 people, residents told AFP. \"As soon as they got in (the town) they blended among traders conducting business,\" resident Ibrahim Bulama said, adding that they later began shooting in a market and killed 15 people. Another local, Aisami Yusuf, also put the death toll at 15.