A rebel commander in the eastern Democratic Republic of Congo is threatening an all-out rebellion against the new national army by Tuesday, unless there is an investigation into recent violence by government soldiers against civilians.

Dissident army leader General Laurent Nkunda says the Congolese national army led by Brigadier General Mbuza Mabe is advancing north from Bukavu.

"The situation is not so good because Mbuza Mabe's troops are advancing on the road from Bukavu to Goma where we are and we were there according to the agreement we have with the government that they are going to send an investigation team," he said. "And before they send this team they are sending troops to come and fight us and this thing is not acceptable because they are soldiers and I have soldiers. What do you think we can do? It is not working."

General Nkunda says the Congolese government must honor the agreement to send an investigative commission to look into the deaths of members of the minority ethnic Tutsi Banyamulenge. More than a dozen civilians were killed in the eastern town of Bukavu at the end of May, allegedly at the hands of government soldiers. General Nkunda says if the commission does not arrive by Tuesday, his fighters will confront General Mabe's troops.

The U.N. spokesman in Bukavu, Sebastien Lapierre, says that in recent days Congolese government forces reclaimed a northern town that had been occupied by Nkunda's men. He says the United Nations is also monitoring recent clashes by dissident troops in the south of Bukavu led by Colonel Jules Mutebutsi who is an ally of General Nkunda.

"There are two fronts at the moment," he said. "There is one north of Bukavu in a town called Kalehe. The government forces reclaimed that town which was still occupied by the Nkunda forces, the rear guard of his column marching northwards. Now the other front is south of Bukavu and there there was fighting and that would be between Mutebutsi's men and the 10th military regiment."

The two rebel commanders seized the town of Bukavu on June 2 and held it for one week, despite the presence of U.N. peacekeepers, leading to anti-U.N. protests throughout the country.