The rebels fought their way along a strategic road towards the town of Rutshuru, around 100 km north of North Kivu’s provincial capital Goma, early on Tuesday, drawing within 10 km of Rutshuru.

“The convoy is being prepared now, but hasn’t left yet,” a spokesman for UN humanitarian coordination agency OCHA said about the evacuation plan.

UN-backed Radio Okapi reported clashes around Kibumba, 20 km north of Goma, which saw heavy exchanges of fire on Monday, when rebel forces said they had forced the Congolese army from their positions there.

Both Rutshuru and Kibumba shelter tens of thousands of internal refugees displaced by years of fighting in east Congo.

An aid worker working with medical charity Medecins Sans Frontieres (MSF) said that its staff in Rutshuru could hear the explosions from its headquarters at the main hospital early on Tuesday as fighting neared the town.

“In Rutshuru, the population is fleeing north. We’ve heard about an evacuation, but for the moment we have no plans to leave,” Axelle de la Motte Saint-Pierre, MSF’s deputy head of mission in North Kivu, said.

She said MSF’s medical team there had treated around 70 people wounded in fighting since the offensive began on Sunday.