Fresh clashes between the Democratic Republic of Congo's military and a group of mutineers has erupted in the eastern province of Nord-Kivu, a day after fierce battles near a rare gorilla park.

"We're on the ground. We've been confronting the FARDC [the Democratic Republic of Congo's military] since this morning 3km from Bunagana ... where we were yesterday," Vianney Kazarana, a spokesman for the mutineers' March 23 Movement (M23), told the AFP news agency.

"The FARDC are using combat tanks. We're resisting. We're at the front, we're facing the enemy."

Al Jazeera’s Nazanine Moshiri, reporting from Bunagana in the DRC, said: "We are seeing and hearing a lot of movement along the road in Bunagana near the Ugandan border.

"We are 5km away from positions belonging to M23, the rebel group which is currently fighting government forces.

"We have seen the government forces maneuvering along this road with pretty heavy weaponry. We saw them with anti-aircraft guns and we believe that they are going to be using anti-aircraft air guns to fire into M23 positions in the hill sides nearby.

The two sides have been mired in back-and-forth clashes in the remote jungle region for weeks.

The mutineers are former rebels who were integrated into the army under a 2009 peace deal but started to defect en masse, complaining of poor treatment.

On Saturday, fighting broke out around 02:00 GMT when M23 attacked army positions in the Rutshuru territory near Virunga National Park on the Ugandan border, home to more than half the world's 700 or so mountain gorillas.