Complex sentence: The Croatian Air Force took part in the attack the same day, using two MiG-21s to conduct airstrikes designed to disrupt the road network around Glamoč, violating a no-fly zone imposed by the UN and enforced by NATO as Operation Deny Flight.
Split into simpler sentences: The Croatian Air Force took part in the attack the same day, using two MiG-21s to conduct airstrikes designed to disrupt road network around Glamoč. The airstrikes were in violation of a no-fly zone imposed by the UN and enforced by NATO as Operation Deny Flight.