On 2 September 1984, Father's Day, the Comancheros and the Bandidos motorcycle gangs waged war against each other at a bike swap meet in Milperra - in what was to become known as The Milperra Massacre.
The bitterness between the Bandidos and the Comancheros grew to such an extent that on 10 August 1984 a bikie war was declared. The presidents of both gangs spoke abrasively to each other over the telephone. The war declaration was officially ratified. If ever the two gangs met, a full scale confrontation could be expected. The bikies armed themselves for the inevitable bloodshed that accompanies any war. Following the Milperra Massacre the NSW police mounted the highly organised by perilous Operation Hard Walk to simultaneously arrest 43 bikies at their homes and charge them with murder. The resulting trial at Penrith Court House was the largest joint trial in NSW judicial history.