An international human rights group says the Burundian army, police and members of the ruling party's youth league executed 47 people following a clash with an armed group in the country's northwest.

Human Rights Watch said Thursday it spoke with more than 50 people, including 32 witnesses to the killings which took place between Dec. 30 and Jan. 3.

Human Rights Watch says the armed group crossed into Burundi from neighboring Congo in late December.

The group says that members of the group surrendered to authorities in January. It says most of those who surrendered were executed. Burundi's government has said fighting with the rebels led to the death of 97 combatants including two soldiers.

There was no immediate comment from the Burundian government.