HARARE, Zimbabwe (AP) — An Islamist group operating in Mozambique’s northern Cabo Delgado province used boys as young as 13 in attacks on a town last week and residents who were forced to flee the fighting recognized some of the child soldiers as their missing relatives, advocacy group Human Rights Watch said Wednesday.

Al-Shabab, which is affiliated to the Islamic State group, has previously been accused by UN agencies of kidnapping children and using them as soldiers in its insurgency in the region, which began in 2017. A surge of attacks by insurgents in March left at least 70 children missing, according to local authorities and a group of aid agencies.

Witnesses told the rights group that dozens of child soldiers were used in the attacks and were seen carrying AK-style assault rifles and ammunition belts. Two people from the same family said they recognized their 13-year-old nephew among the children.