tand now, that multinational taskforce has left," he said.
Refugees told aid workers that Boko Haram fighters had "promised to return to Rann", he said, explaining the panic.
Baloch said UNHCR was reiterating its call to Cameroonian authorities "to keep the borders open, as we see thousands fleeing every day".
Baloch said a recent upsurge in violence in northeastern Nigeria had driven more than 80,000 civilians to seek refuge in already crowded camps or in towns in Borno state, "where they are surviving in tough living conditions".
Rann, he said, had already been housing about 80,000 displaced people.
"The escalation in the conflict has thwarted people's intention of returning to their homes," he said, adding some refugees who attempted to return home from Cameroon had been displaced multiple times inside Nigeria or forced to become refugees again in Cameroon.
"The hostilities have strained humanitarian operations there and forced aid workers to pull out from some locations," he said.
Jens Laerke, spokesman for the UN humanitarian agency, told reporters that 260 aid workers were withdrawn from three locations in Borno state since early December.