At least five Congolese soldiers have been killed in a gun battle between soldiers from the Democratic Republic of Congo (DRC) and Rwandan forces on their volatile border, local Congolese officials have said.

Wednesday's fighting began in northeast of the provincial capital Goma after Rwandan troops crossed the border into DRC's restive province of North Kivu and abducted a Congolese soldier, according to a DRC army spokesman.

The spokesman later confirmed the abducted corporal had been killed and blamed Rwandan troops.

Later on Wednesday, Rwanda accused DRC's soldiers of crossing the border into its territory and opening fire on Rwandan soldiers in battles that left four more dead.

"On Wednesday ... a section of the DRC army crossed the border to Rwanda where they opened fired on a Rwanda Defense Force (RDF) patrol," the government said in a statement.

"The attacks in the morning were followed by a second attempt: a deployment of two FARDC (Congolese) platoons to Rwanda, which led to a new firefight that killed four FARDC soldiers."

Louise Mushikiwabo, Rwandan foreign minister, said the country stood "ready to act to protect its citizens" against further attacks.

"These actions by the DRC are jeopardising the region's extensive efforts to ensure peace, stability and development for all our citizens," Mushikiwabo said 

Threat to stability

Renewed tensions between the two neighbours may undermine international efforts to bring stability to Congo's mineral-rich, lawless east and the wider region after years of conflict.

General Carlos Alberto dos Santos Cruz, commander of UN peacekeepers in Congo, told a news conference on Wednesday that the fighting had taken place and said the United Nations would investigate the clash.

Kigali and Kinshasa have long been at odds, with Rwanda accused by the UN of backing rebels in DRC.

Rwanda fought against the central government in Kinshasa in Congo's two wars in 1996-97 and 1998-2003 and has been involved in several attempts to destabilise the country, backing uprisings by Tutsi-dominated rebels.

However, since the defeat in November of a Kigali-backed rebellion led by the M23 group, the border has remained relatively calm.

Source: Agencies