ZURICH - Rebels in the Democratic Republic of Congo strapped explosive belts around baby twin girls as a booby-trap for security forces - just one incident in a surge in violence against children there, the United Nations said on Friday.

The two girls, aged one-year-old, were found in a village in north Kivu, a region where a militant group known as the Allied Democratic Forces (ADF) has stepped up bomb attacks, the UNICEF children's agency said. The explosives were removed by mine experts without detonating.

"The intention was with the arrival of police or Congolese military they would trigger the explosion against the security forces," Grant Leaity, the UNICEF representative in Congo, told a media briefing in Geneva.

The increased use of improvised explosive devices was just one of several "depraved trends" as violence against children reaches unprecedented levels in the eastern part of Congo, he said.

"On a daily basis, children are being raped and killed. They are being abducted, recruited and used by armed groups – and we know the reports we have are only the tip of the iceberg," he said.

The violence in Congo has caused one of the world's worst and longest-running humanitarian emergencies, with more than 27 million people facing food shortages, and nearly 5.5 million forced to flee their homes, according to the U.N. More than 2.8 million children are bearing the brunt of the crisis.

The twin sisters, who have not been identified, are now recovering from malnutrition at a U.N. centre before being placed in foster care. Their parents had been killed in an attack believed have been carried out by the ADF.

Although making a good recovery from malnutrition, the mental scars could last a life-time, Leaity said.

"You would not be able to imagine what they have been through," he added. REUTERS