Attackers killed scores of people at a Congo church during Christmas.
The U.N. said at least 189 people were been killed in a series of attacks on villages near the Sudan and Ugandan borders.
The first attack took place during a Christmas day concert organized by a Catholic church.
Two priests were reportedly killed and a church was burned to the ground.
The Catholic Relief Agency Caritas has workers in the area.
Bruno Miteyo, country director of the group, described the scene as told to him by his staff.
"People were there celebrating Christmas, listening to the music and dancing," he began. "The rebels, they came, it was a kind of surprise, and they're being killed. And on the following day, on the 26th, they came very early in the morning and they killed 150 people."
Miteyo said a doctor working for Caritas and his wife also died in the attacks.
The Lord's Resistance Army, a Ugandan rebel group, was blamed for the attacks, but the group denied responsibility.
About 25,000 people have fled the area and are in hiding in the mountains.