KAMPALA, Uganda (AP) — Human Rights Watch says over 155 people died last November in deadly encounters between Ugandan forces and people loyal to a tribal king who has since been charged with treason.

The group said in a statement Wednesday that some children were killed and called for an investigation by international experts into the killings, which followed tensions between President Yoweri Museveni's government and the leader of a tiny mountain ceremonial kingdom known as the Rwenzururu.

The government charges that the traditional king, Charles Wesley Mumbere, led armed tribesmen who threatened state security in a series of violent encounters near Uganda's border with Congo.

Human Rights Watch says the king's men, armed with tools like machetes, would not constitute an armed group under international humanitarian law.