After killing at least 40 people in their latest series of raids on villages in northern Nigeria this week, Boko Haram militants appear to have Maiduguri and its 2 million residents surrounded. From CBC News: “In Maiduguri, some 200 kilometers north of Michika, people fleeing militant attacks in neighboring Borno state say that Boko Haram fighters warned they are preparing ‘a big grave’ for them in Maiduguri and that ‘there will be no mercy.’” Though Nigerian military forces were able to fight off Boko Haram militants this weekend in Maiduguri, there are reports that the city is now surrounded and several roads in have been taken over Boko Haram. Authorities fear that the terrorist group my be planning a massive attack soon …