(BBC News) Around 40 people, mostly pupils, have been killed at a school in western Uganda by rebels linked to the Islamic State group (IS).
A further eight people remain in a critical condition after the attack on Lhubiriha secondary school in Mpondwe.
Boys staying in dormitories are among the dead. Several others, mostly girls, have been abducted, authorities say.
The Allied Democratic Forces (ADF) — based in the Democratic Republic of Congo (DRC) — have been blamed.
The attack happened at around 23:30 (20:30 GMT) on Friday at the school in the Kasese district in western Uganda.
Over 60 people are educated at the school, most of whom live there.
Some five suspected ADF rebels carried out the attack, burning the school buildings and looting the food store, the Ugandan army has said.
Some of the boys were burnt or hacked to death, Maj Gen Dick Olum from the army said.
Survivors told local media that the attackers used machetes against the students before throwing a bomb into a dormitory.
The ages of the victims are not known.
Photos of burning buildings at the school have circulated on social media.
Members of the wider community are possibly among the dead. A number of students remain unaccounted for, and the number of those who died is unclear.
Soldiers are pursuing ADF insurgents towards the DRC’s Virunga national park — Africa’s oldest and largest national park that is home to rare species, including mountain gorillas.
Militias including the ADF use the vast expanse, which borders Uganda and Rwanda, as a hideout.
“Our forces are pursuing the enemy to rescue those abducted and destroy this group,” defence spokesperson Felix Kulayigye said on Twitter.
The Ugandan army has deployed helicopters to help track the rebel group over mountainous terrain.