U.N. peacekeepers killed four Congolese dissident fighters on Sunday, pushing them out of a town they had overrun in a four-day offensive that has forced 50,000 people from their homes, a U.N. official said, according to Reuters. Fighters loyal to renegade ex-army commander Laurent Nkunda, who reject a peace process to end Democratic Republic of Congo's five-year war, began an offensive in the east of the country on Thursday and have briefly occupied a number of towns and villages in cat-and-mouse fighting with the army. The fighters attacked 80 Indian U.N. peacekeepers who were heading to the town of Rwindi on Sunday, about 150 km (95 miles) north of the eastern town of Goma, after government troops were overrun on Saturday. "Four insurgents were killed and three others were captured during the fighting today. They will be questioned so we will know more later," Lieutenant Colonel Mayank Awasthi, a U.N. military spokesman for the North Kivu brigade, told Reuters. U.N. peacekeepers were in control of Rwindi after the attack by about 40 fighters, who used mortars and automatic weapons. Awasthi said there were no injuries on the U.N. side. U.N. staff said about 55,000 people have fled their homes after the fighting, some crossing into neighbouring Uganda, but an aid worker on the ground said the figure was much higher. "This recent fighting has displaced about 80,000 people including some cross border movement into Uganda," the aid worker told Reuters.