KAMPALA, Uganda - Attackers hacked to death scores of people who sought refuge at a Catholic church in remote eastern Congo the day after Christmas, officials and witnesses said Monday.

The Ugandan army and a rebel group accused each other of carrying out the massacre.

Survivors and witnesses said the killings occurred close to Congo's border with Sudan, near to where the armies of those two countries and Uganda began an offensive this month to root out the rebel Lord's Resistance Army, according to Ugandan army spokesman Capt. Chris Magezi.

A United Nations spokesman, Ivo Brandau, said 120 homes were set ablaze in the area and that thousands of people have fled for fear of further attacks.

The LRA has waged one of Africa's longest and most brutal wars for the past two decades. In the past, aid and human rights groups have accused the rebels of cutting off the lips of civilians and forcing thousands of children to serve as soldiers or sex slaves. The conflict has spilled out of northern Uganda and into Sudan and Congo.

"The scene at the church was unbelievable. It was horrendous. On the floor were dead bodies of mostly women and children cut in pieces," Magezi told The Associated Press. He blamed the LRA for the massacre and quoted witnesses as saying the rebels used machetes, clubs and swords in Friday's attack.

The rebels denied responsibility, with their spokesman David Matsanga saying the group had no fighters in the area and accusing Uganda's army of the killings.

But witness Abel Longi said he recognized the rebels by their dreadlocked hair, their Acholi language and the number of young boys among them. "I hid in bush near the church and heard people wailing as they were being cut with machetes," Longi told The AP in a telephone call from the village of Doruma, where the church is located. He owns a shop there.

Death toll estimates varied, in part because the area is so remote.

A European aid worker said more than 100 people are reported to have been killed in the attack, and the Congolese military put the number of dead at 120 to 150. Magezi said 45 civilians were killed. The aid worker spoke on condition of anonymity because his organization fears reprisals.

UN-run Radio Okapi quoted the governor of Congo's Oriental Province, Medard Autsai Senga, as saying the death toll had surpassed 75 and that bodies still were being discovered around the church. He appealed for aid for survivors.

The UN said the rebels killed 189 people in three villages over two days, 89 of them at Doruma.

The rebels may have been retaliating against civilians for military attacks, including a Dec. 14 air bombing on their main camp in Garamba National Park.

Rebel spokesman Matsanga claimed in a telephone interview from Nairobi, Kenya, that Uganda's 105th Battalion was responsible for the massacre. "They were airlifted to Congo to kill civilians and then say we are responsible," he charged. "They want to justify their stay in DRC (Congo) and loot minerals from there like they did before."

Congo suffered back-to-back civil wars from 1996 to 2002 that drew in neighbouring countries in what became a rush to plunder Congo's massive mineral wealth.

Currently, long-running peace talks between the LRA and the Ugandan government have stalled.

Rebel leaders have sought guarantees they will not be arrested under international warrants. The rebels' elusive leader, Joseph Kony, and other top members are wanted by the International Criminal Court in The Hague for war crimes and crimes against humanity.