Government forces launched the assault on fighters loyal to dissident Tutsi General Laurent Nkunda late on Sunday near Karuba, some 30 km (19 miles) west of Goma, the capital of North Kivu province.

Exchanges of machine gun and heavy weapons fire lasted several hours with clashes continuing throughout Monday morning, army officials said.

"Up to now these are preventative strikes designed to allow us to control the terrain," the army's commander of operations, Colonel Delphin Kahimbi, told Reuters, adding that the bodies of 28 Nkunda loyalists were recovered following the attacks.

No independent verification of the death toll was immediately available.

The clashes came as Rwanda's Foreign Minister Charles Murigande visited Kinshasa to meet his Congolese counterpart Antipas Mbusa Nyamwisi as part of bilateral efforts to prevent the fighting from developing into a broader conflict.

Relations between former enemies DRC and Rwanda remain cool four years after the end of Congo's 1998-2003 war.

Rwanda has twice invaded its giant western neighbour, first in 1996 and again in 1998, in pursuit of Hutu rebels it accuses of carrying out the 1994 Rwandan genocide that killed an estimated 800 000 Tutsis and moderate Hutus.

Murigande's visit was the first by a Rwandan foreign minister for three years.

RWANDAN MEDIATION

Monday's clashes follow more than a week of on and off fighting in North Kivu. On Thursday, about 1 000 Nkunda loyalists attacked a government army brigade headquarters.

Rwanda mediated in talks in January between Congolese officials and Nkunda that led to the creation of five special mixed government brigades aimed at bringing the renegade general's fighters back into the ranks of the army.

It is from those mixed brigades that Nkunda loyalists have deserted in recent weeks.

Murigande again offered Rwandan mediation in dealing with Nkunda but said the Congolese must first deal with the problem of the Hutu-dominated Democratic Forces for the Liberation of Rwanda (FDLR), a rebel group with bases in eastern DRC.

"It is my ardent hope that this visit will lead to a renewed commitment by the government of the DRC to track down, disarm, demobilise and repatriate the remaining (FDLR)," he said.

DRCs Defence Minister Chikez Diemu has called for a peaceful resolution to the worsening situation in North Kivu, but at the weekend warned Nkunda's fighters they would be treated as bandits if they refused to reintegrate into the army.

Kahimbi said further operations against the renegades, which split from special army brigades late last month, were possible.

"We are in the middle of a force mobilisation. Soon we will be able to broaden operations with all the necessary support," he said.