Forty-one people, including 38 students, were shot, burned or hacked to death by suspected militants at a secondary school in Uganda’s Mpondwe-Lhubiriha city on Friday, Mayor Selevest Mapoze told The Associated Press.

The militants also allegedly kidnap six people in the border town and fled to Congo, the Ugandan military said. The police said eight other people sustained critical injuries in the attack, reported Reuters.

The authorities have accused the Allied Democratic Forces, a militant group that his ties with the Islamic State, according to the news agency. This is one of the worst attacks in the country over a decade, according to AFP.

The victims of the massacre include the students, one guard and two members of the local community, Mapoze told AP. The mayor also said that some other students sustained fatal burns when the rebels set fire to a dormitory.

Joe Walusimbi, an official representing the president, told AP that some of the victims “were burnt beyond recognition”.

The militant group has been accused of launching many attacks in recent years while targeting civilians in eastern Congo but has rarely claimed responsibility, reported the news agency.

In March, 19 civilians were killed in Congo by suspected Allied Democratic Forces militants.