"Eighty thousand people left the camps although the attack did not take place," said Jean-Marc Mambidi, a member of the UN World Health Organization (WHO) team in the province. Kiwanja is located 63 km from Goma.
Some of the IDPs, who fled after rumours of an attack by Mai Mai militia on 19 November, were staying with other families while the rest remained without shelter, Mambidi said.
The IDPs had earlier fled fighting between renegade army General Laurent Nkunda's Congres national pour la defense du people (CNDP) rebels and pro-government forces.
The UN World Food Programme had to suspend a food distribution exercise scheduled in the area because the expected beneficiaries were no longer there.
Relative calm continued to prevail in the area despite reports of skirmishes in some places, according to the UN Mission in Congo (MONUC).
However, MONUC troops were twice been forced to return fire after Mai Mai attacks, said spokesman Madnoje Mounoubai.
MONUC also condemned the looting of a therapeutic nutrition centre run by the Lutheran World Federation (LWF) in the area of Kayna, 200 km from Goma.
Meanwhile, road repairs were being carried out near Goma so that some 65,000 IDPs in one camp near the frontline can be moved to a safer site.