Trucks rumbled out of the capital of Kinshasa Monday, loaded with government troops on their way to reinforce fighters battling rebels in western Congo, a radio report said.

President Laurent Kabila had ordered the reinforcements to try to retake several small towns in the west, including the oil town of Muanda, state-controlled radio reported.In their weeklong uprising against Kabila, rebel Tutsis have captured strategic towns in both the west, about 150 miles southwest of Kinshasa, and in Congo's eastern Kivu region.

On Sunday, Kabila's government accused Uganda of sending soldiers and tanks into Congo in support of the Tutsi rebellion.

The government also accused neighboring Rwanda, which it alleges instigated the uprising, of executing Congolese army officers and rounding up civilians in the region.

The charges could not be independently confirmed, but if true, they represent a sharp escalation in hostilities that threaten to spawn a broader regional conflict.

Tutsi gunmen with close ties to Rwanda launched an offensive a week ago in Kivu, vowing to topple Kabila's 14-month-old regime. With-in the first few days of their uprising, the rebels captured several key cities near the Rwandan border.

Information Minister Didier Mumengi said Sunday that Congolese forces reported at least 10 Ugandan tanks and seven trucks with soldiers heading toward Bunia.

Kabila has recently accused Rwanda of trying to establish a "Tutsi empire" in his territory, charges that Rwanda has denied. An edgy Rwanda has vowed to fire back at Congo if attacked and more recently has warned of a possible pre-emptive strike.

In another sign of the growing instability in eastern Congo, more than 60 foreign aid workers in Bukavu fled across the border into Rwanda over the weekend, state-controlled radio in Rwanda reported. They included Americans, Canadians and Belgians.

Meanwhile, Congo's government appeared to be gearing up for a protracted fight: It increased security around Kinshasa, closing all river ports and halting traffic across its river border with the Republic of Congo.

Talks over the weekend in Victoria Falls, Zimbabwe, made little progress toward ending the hostilities. Rwandan President Pasteur Bizimungu accused Kabila of seeking a pretext to attack Rwanda.

He said Rwanda had evidence that Kabila's forces had been training former Hutu soldiers and militiamen in the southern city of Kamina, and have plans to use them against Rwanda.