Fighting picked up on Friday in eastern Democratic Republic of Congo between the M23 rebel group and the Congolese army, a rebel leader, military sources and civilians told Reuters.
Clashes had subsided for about a week since the M23's latest offensive in late October. The rebel group has had a major resurgence this year, forcing tens of thousands of people to flee their homes, after its first big insurrection in 2012/13.
The fighting has caused a diplomatic rift between Congo and neighbouring Rwanda, which Congo accuses of backing the M23. Rwanda denies this.
"We are currently shelling their positions and we are going to take back the localities under the control of the M23," said a senior army officer on condition of anonymity.
Fighting was reported on several fronts in Rutshuru territory, in east Congo's North Kivu province, on Friday morning. Some of the clashes were in Virunga National Park near the towns of Kiwanja and Rutshuru, civilians and the M23 said.
Congo's army spokesman for North Kivu declined to comment.
One of the leaders of the M23, Bertrand Bisimwa, said on Twitter that fighting had resumed and accused the Congolese army of working with another rebel group, the Forces for the Liberation of Rwanda (FDLR), and various local militias. Congo has denied backing the FDLR.
The conflict stems from the long fallout from the 1994 genocide in Rwanda. The M23 group is Tutsi-led, while the FDLR is composed of ethnic Hutus.
Officials from Democratic Republic of Congo and Rwanda held talks on Saturday in Angola aimed at easing political tensions caused by the conflict.
(Reporting by Kinshasa Newsroom; Writing by Nellie Peyton; Editing by Anait Miridzhanian and Toby Chopra)
