People walk in a street as smoke rises after Boko Haram Islamists attacked a military base in the northeast Nigerian city of Maiduguri on March 14, 2014. The gunmen freed dozens of insurgents from custody, the military said of the latest raid in the embattled city.  The attack is another blow to the military's campaign against the extremist group, which has been blamed for thousands of killings since 2009 in Africa's most populous country and top oil producer. AFP PHOTO/STRINGER

        (Photo credit should read STR/AFP/Getty Images)