Fighters from the Islamic extremist group grow more bold.
The expansion of Boko Haram's reach came as neighboring countries are fighting back with ground troops and aircraft, with even greater military strikes by more countries planned. The U.S. strongly condemned the Boko Haram attacks and pledged continuing assistance to fight the militants.
Boko Haram has openly threatened to attack other countries taking part in the military effort to subdue their insurgency, blamed for 10,000 deaths over the past year. Cameroon, Niger, Chad and Benin all have pledged to send troops to fight Boko Haram, which has waged a five-year rebellion against the Nigerian government.