According to the book "Among Friends: The Scots Guards 1956-1993" ...
....two members of C Company absconded from their posts on the border and attempted to hijack an aircraft at Kai Tak airport; they were eventually talked out of taking such action by a Hong Kong Police Officer and no damage was done other than to the battalion's reputation which regrettably never recovered with the Colony media who were understandably critical. For their part the military authorities played the incident in a low key leaving Colonel Ross to sort matters out within the battalion.