As part of a deception plan, a Douglas DC-8 airliner was flown over the Chimoio camps 10 minutes before the airstrike; the assembled ZANLA forces assumed a second false alarm, and did not disperse or try to take cover when the bombers subsequently approached.[5] In the first pass, four Canberra bombers dropped 1200 Alpha bombs (Rhodesian-designed anti-personnel bombs) over an area 1.1 kilometres (0.68 mi) long and 500 metres (1,600 ft) wide.[6]