Expanding extremist groups in Africa fuel worries that they could attack the US or Western allies

Violent extremist groups linked to al-Qaida and the Islamic State group are growing in size and influence across Africa, fueling worries that as they improve their tactics, they could attack the U.S. or Western allies. U.S. defense and military officials are describing the threats and their concerns about growing instability in Africa, where a number of coups have put ruling juntas in control, leading to the ouster of American troops and a decline in U.S. intelligence gathering. They are speaking Tuesday at a conference of African chiefs of defense in Botswana.