Last week, militant group al-Shabab attacked a shopping mall in Nairobi, Kenya, killing over 60 people. On Sunday, dozens of students were murdered when a group, widely believed to be Boko Haram, rampaged an agricultural college in northeast Nigeria. David Hyde talks with Peter Lewis, director of Johns Hopkins' African studies program in their School of Advanced International Studies, about extremist violence in Africa and the different groups operating there.
Produced by Hannah Burn.
