As many as 65,000 people have fled violence in the northeastern Nigerian town of Damasak, the United Nations said on Friday.
The so-called Islamic State West Africa Province group unleashed a series of attacks in Borno state, looting and burning homes, warehouses of humanitarian agencies, a police station, a clinic and also a UNHCR facility.
"Up to 80 percent of the town's population — which includes the local community and internally displaced people as well — were forced to flee," said Babar Baloch, Spokesperson for UNHCR.
ISWAP, split from Boko Haram in 2016 and has become a dominant threat in Nigeria.
More than 36,000 have been killed and two million displaced by the decade-long fighting in Nigeria that has spread into neighbouring Chad, Cameroon and Niger.
Some have fled towards the regional capital Maiduguri and other nearby towns while others have crossed the border into Niger's Diffa region, itself vulnerable to jihadist violence.
"The people of Damasak are desirous to stay in Damasak. However because of the security situation, some have fled into the bush, some have fled into neighbouring Niger for safety," said Abubakar Kyari, Senator representing Borno North.
Nigeria's army dismissed reports militants had overrun Damasak and said on Thursday troops were in control of the area.
At least four people, including a soldier, were killed in an attack Monday. The UN said eight others were killed Wednesday, while locals said ten bodies were buried and 20 people were injured.
The town hosts one of the military's fortified garrisons or so-called "super camps" to fend off attacks.
But critics say closing smaller bases for the leârger camps has left jihadists freer to roam in rural areas.