premise: UN peacekeeping forces in the Democratic Republic of Congo (DRC) and government troops have driven rebel soldiers out of an eastern town they had captured at the weekend, the UN mission announced Monday.
  The UN mission, known by its French acronym MONUC, said that its blue helmets (UN forces), fighting alongside the National Army Force in the DRC (FARDC), launched air strikes on the rebel 81st and the 83rd brigades loyal to General Laurent Nkunda.
  The rebel soldiers began to retreat from the town of Sake under the pressure of UN attack helicopters and ground forces. The MONUC suffered no casualties, it said.
  Nkunda's men launched attacks on Saturday, taking the town of Sake which is close to Goma, the chief town of North-Kivu province. The FARDC formed its defense at Kazingani, a few kilometers to the east of Sake, after abandoning the town on Sunday. The fighting has killed eight people.
   What events were a part of the fighting undertaken by the UN forces?
hypothesis: launched air strikes on the rebel 81st and the 83rd brigades