Why did Cameroon join a multinational force against Boko Haram in 2015?

Cameroon joined a multinational force in 2015 to enhance the coordination of efforts to combat and eradicate the Boko Haram Islamic militant group from the region.12

By early 2013, Cameroon had been drawn into the conflict occurring in neighboring Nigeria as the militant group began making incursions across the border, targeting Cameroon with attacks and kidnappings. Because the Cameroonian military had experienced only limited success in countering these threats independently, the country joined forces with other nearby nations in a coalition approved by the African Union to improve the effectiveness of their military response.12