A series of battles followed at Uijeongbu on 1 – 4 January 1951 , as the British and Australians occupied defensive positions in an attempt to secure the northern approaches to the South Korean capital . Further fighting occurred at Chuam @-@ ni on 14 – 17 February 1951 following another Chinese advance , and later at Maehwa @-@ San between 7 – 12 March 1951 as the UN resumed the offensive . Australian troops subsequently participated in two more major battles in 1951 , with the first taking place during fighting which later became known as the Battle of Kapyong . On 22 April , Chinese forces attacked the Kapyong valley and forced the South Korean defenders to withdraw . Australian and Canadian troops were ordered to halt this Chinese advance . After a night of fighting the Australians recaptured their positions , at the cost of 32 men killed and 59 wounded . In July 1951 , the Australian battalion became part of the combined Canadian , British , Australian , New Zealand , and Indian 1st Commonwealth Division . The second major battle took place during Operation Commando and occurred after the Chinese attacked a salient in a bend of the Imjin River . The 1st Commonwealth Division counter @-@ attacked on 3 October , capturing a number of objectives including Hill 355 and Hill 317 during the Battle of Maryang San ; after five days the Chinese retreated . Australian casualties included 20 dead and 104 wounded .