Z Force [????-????]
"Z Force" was a band of local volunteers which had been trained beforehand for work behind the Japanese lines and was led by Mr Kendall. Dumps of arms, supplies, medical stores, etc had been made beforehand at three points in the New Territories.
Quoted from http://www.hongkongescape.org/Kendall.htm, which has more information about Z Force.
One of its members was Colin McEwan, and the early section of his wartime diary describes some of Z Force's activities.