Geneva - Thousands of refugees are fleeing harrowing scenes of atrocities and body-strewn streets in northern Nigeria, the UN said Tuesday.
The UN's refugee agency said violence in the area had prompted some 2,000 people to flee into neighbouring Niger over the past four weeks alone.
UNHCR spokesman Adrian Edwards said refugees arriving in Niger's Differ region, as well as Cameroon and Chad, were speaking of "atrocities", with one woman describing "corpses strewn through houses and floating in the water."
The woman told UNHCR staff that people feared staying even to bury their dead or find missing relatives, Edwards said, adding that others reported kidnappings of women and children.
He said it was not possible to identify the assailants.
However, violence by Boko Haram militants that has raged in northern Nigeria since 2009 is known to have become particularly ferocious in recent weeks, with some 500 people killed in suspected Islamist attacks since the start of the year.
"UNHCR reiterates to all parties to the conflict in northeastern Nigeria the vital importance of protecting civilians from harm," Edwards said.
He pointed out that the insurgency in the three northeastern Nigerian states of Yobe, Adamawa and Borno had already displaced more than 470,000 people inside the country.
"Clearly this is an escalating crisis," he said, pointing out that it was also difficult for aid workers and others to access the displaced.
"The ability of any of the international community to help inside that area is definitely constrained at the moment," he said.
In addition, more than 57,000 people have fled to Cameroon, Chad and especially to Niger, which had taken in a full 40,000.