More than 107 000 people have been displaced in Mozambique in the past fortnight by rising violence in the north of the country and some aid supplies are running out, the United Nations humanitarian agency said on Friday.

Attacks by insurgents in northern Mozambique have increased this year, spreading into previously safe areas and beyond the gas-rich Cabo Delgado to the provinces of Nampula and Niassa.

The violence has displaced more than 1.3-million people since 2017, according to the UN.

"People flee because their villages are attacked and burned and destroyed, and others flee in surrounding villages for fear of attacks," Paola Emerson, Head of Office at the UN Office for the Coordination of Humanitarian Affairs (OCHA) in Mozambique, told reporters in Geneva via video link from Maputo.

The UN says some 107 000 people have left their homes in Nampula city due to spreading violence. Over the last four months a total of 330 000 people have been displaced.

"This latest wave that is taking place in Nampula is unusual, as we've seen reports of non-state armed groups' attacks lasting now for a couple of weeks, whereas the pattern in the past was more in and out," Emerson said.

Attacks have also included renewed violence in Cabo Delgado's Palma District for the first time since 2021, a report by UN children's agency UNICEF noted on Tuesday. It reported killings of civilians in multiple districts, and targeted assaults on security forces.

OCHA warned that food stocks and health kits were running out. About 40% of those displaced have received food for the next two weeks, the agency added.

"But this is woefully inadequate," Emerson said. In spite of continuing security risks in areas they had fled from, "in some instances it's also forcing returns as people are not receiving assistance where they are currently," she said.