The United States has concluded a joint operation with Nigerian forces against Islamic State (IS) militants in the Lake Chad Basin area, which began in December 2021. This operation included strikes against IS militants on Christmas Day and the deployment of approximately 200 soldiers two months later. Notably, senior IS leader Abu-Bilal al-Minuki was killed during this mission. On Thursday, the US announced the operation as a success, while Nigeria's military spokesperson expressed confidence that the withdrawal of US troops would not impede their progress in combating militants. Despite these operations, jihadist groups continue to carry out attacks, particularly in north-eastern Nigeria. The intelligence-sharing between the two countries will persist, according to both nations' military officials. This increased cooperation followed concerns raised by Washington about insufficient protection of vulnerable groups by Nigerian authorities and allegations of a "Christian genocide" in the country, which were firmly rejected by Nigeria. IS has significantly shifted its focus in recent years, with around 90% of attacks now occurring in sub-Saharan Africa, predominantly by its Nigeria-based branch, the most active of all. The joint operation disrupted IS's local command structure and global network, limiting their communication abilities. US military personnel stationed in Nigeria before the Lake Chad Basin operation have remained in the country. Nigeria faces various security challenges, including not only Islamist militants but also banditry and criminal violence that has spread from the north into central and southern regions of the country. For more African news, visit BBCAfrica.com, follow us on Twitter @BBCAfrica, Facebook at BBC Africa, or Instagram at bbcafrica.