File Maiduguri, Nigeria: US offers $7mln for Boko Haram head In an unprecedented move, the United States on Monday posted up to $23 million in rewards to help track down five leaders of militant groups accused of spreading terror in west Africa. The highest reward of $7 million is offered for the Boko Haram leader Abubakar Shekau, who last week called on Islamists in Afghanistan, Pakistan and Iraq to join the bloody fight to create an Islamic state in Nigeria. Recent file images of the conflict in city of northeastern city of Maiduguri (a flashpoint of the fight against Boko Haram) and of Boko Haram.