In October 2017, members of the Islamic State in the Greater Sahara, or ISGS, ambushed American troops near the border of the Sahelian states of Mali and Niger, killing four U.S. soldiers and wounding two others. Just after the attack, AFRICOM claimed the troops were providing “advice and assistance” to local partners, but it was later revealed that American commandos operating alongside a Nigerian force had — until poor weather intervened — hoped to link up with another contingent of U.S. special operators trying to kill or capture Islamic State leader Doundoun Cheffou.

Despite these and several other long-running U.S. military efforts in the region, militant groups in the Sahel have grown more active and their attacks more frequent, according to the Africa Center. In fact, “violent episodes” linked to groups associated with Al Qaeda in the Islamic Maghreb, or AQIM, and ISGS increased from 192 in 2017 to 464 last year. At the same time, fatalities linked to these groups more than doubled, from 529 to 1,112.

This is especially significant in light of a 2000 report prepared under the auspices of the U.S. Army War College’s Strategic Studies Institute, which examined the “African security environment.” While noting the existence of “internal separatist or rebel movements” in “weak states,” as well as militias and “warlord armies,” it made no mention of Islamic extremism or major transnational terror threats. Now the Africa Center counts 24 “active militant Islamist groups” on the continent while other official tallies have, in recent years, put the figure at nearly 50 terrorist organizations and “illicit groups” of all types.

Neither the Pentagon nor AFRICOM responded to The Intercept’s questions about the Africa Center’s analysis, the command’s effectiveness, and any role it may have played in the rising violence on the continent.