Hundreds of Boko Haram militants attacked an Air Force base and a military checkpoint in the northeastern Nigerian city of Maiduguri early Monday , according to government officials . Loud explosions were heard between 3 and 4 a.m. and several ambulances were seen leaving the base . The number of casualties is unknown . The governor of Borno state has imposed a strict 24-hour curfew forcing citizens to remain indoors and all air traffic in the state has been halted . Borno is one of three embattled states in northeastern Nigeria that have been under a state of emergency since May as the region is the hotbed for Boko Haram Islamists trying to impose a strict version of Sharia , or Islamic law . Last week Human Rights Watch said Boko Haram has abducted scores of women and girls and used children as young as 13 in their campaign of violence . The report says Boko Haram has killed 3,000 people since 2009 . Cameroon blames Boko Haram in French priest 's kidnapping . U.S. designates Boko Haram , its offshoot as terrorist as organizations .
Boko Haram militants attacked an air base in Maiduguri early Monday . The Nigerian government issued at 24 hours curfew forcing people to stay inside . A woman is carried away from the scene of a suicide bombing attack on a bus carrying passengers leaving Abuja for Kaduna state, Nigeria December 19, 2015.