At least 41 people – mostly teenagers – were killed in a Ugandan high school massacre on Friday night. About 20 members of an ISIS-linked rebel group called the Allied Democratic Forces (ADF) have been accused of killing 37 students, a guard and 3 local community members at the Lhubiriha school (near Uganda’s border with Congo) before abducting another 6 students. The details are pretty grisly – suffice to say the school was set alight, and there are fears more bodies could be found inside. Reports say the ADF is responsible for several similar attacks on civilians – including one last week – in the eastern Congo, despite regular efforts by the Congolese and Ugandan militaries to stop them… And one expert says the extremist group might have targeted the school for shock value. United Nations Secretary-General Antonio Guterres condemned the “appalling attack” and called for the release of those abducted.