Battle of Nui Le The Battle of Nui Le ( 21 September 1971 ) was the last major battle fought by the Australian Army in South Vietnam . The battle was fought between ' B ' and ' D ' Companies of the 4RAR / NZ ( ANZAC ) Battalion ( 4 RAR / NZ ) and elements of the 33rd Regiment of the North Vietnamese Army in Phuoc Tuy Province during Operation Ivanhoe . Background . The decision for the Australian withdrawal from Vietnam , was made by the Australian Government and commenced in November 1970 , and combat forces were to be reduced gradually during 1971 . Intelligence pointed towards a major buildup of Vietcong and North Vietnamese Army forces in the north of Phước Tuy Province and abductions and assassinations had increased in the adjacent Long Khanh Province . The Vietcong and North Vietnamese were preparing for the withdrawal of the 1st Australian Task Force from Phước Tuy Province , which was gradually being withdrawn from August 1971 , and were hoping to defeat the Australians . Prelude . 4 RAR / NZ was committed to a reconnaissance in force operation , named Operation Ivanhoe against any North Vietnamese or Viet Cong forces in the north of Phuoc Tuy Province . D Company , 3rd Battalion , Royal Australian Regiment , 1st Troop , A Squadron , 3rd Cavalry Regiment , 4th Troop , C Squadron , 3rd Cavalry Regiment , 2 Troop , 104th Field Battery , elements of 104th Signal Squadron and 161st ( Independent ) Recce Squadron were also committed to the operation . North Vietnamese Army forces fired rockets and mortars at a South Vietnamese Regional Force outpost at Cam My on Route 2 on 19 September 1971 . The Australian M113 armored personnel carrier s sent to investigate and relieve the outpost were ambushed and came under attack from rocket propelled grenades and small arms fire from what was considered to be large force . 11 Platoon of D Company 4 RAR / NZ made contact with an enemy platoon on 20 September and after a half hour skirmish , four dead enemy soldiers were found on the battlefield . Their uniforms and equipment and study of the tactics used during the skirmish pointed toward the unit being from the North Vietnamese Army . Tracks made by the enemy force indicated about two hundred soldiers had passed through the area . The commander of the 33rd Regiment NVA set a number of ambushes for the expected Australian relief forces , however the Australians did not follow the route that was expected by the North Vietnamese and the Australian went around the ambush sites . Battle . Patrols by 11 Platoon , D Company 4 RAR / NZ on the morning of the 21 September , found sawn logs near the south eastern part of the Courtenay rubber plantation which suggested that there were major fortified bunker positions nearby . B and D Company 4 RAR / NZ moved forward near Nui Le to attack these fortifications . 12 Platoon , D Company 4 RAR / NZ made first contact with a bunker system , suffering one dead from a rocket propelled grenade and four wounded . An estimated platoon strength assault attacked 11 Platoon , D Company 4 RAR / NZ and after a 15 - minute firefight the enemy forces withdrew to their bunkers after removing their dead and wounded form the battlefield . The Australian platoons were ordered to withdraw to an area to the south so airstrikes and artillery could be called in to soften up the bunker systems . United States Air Force air strikes were called in and F - 4 Phantoms and A37 Dragonflys bombed the area with napalm , air to surface missiles , flechette and 500 pound bombs . Iroquois and Cobra helicopter gunships and artillery strikes also hit the bunker system . Pilots reported enemy forces fleeing to the north . At 14 : 00 , D Company 4 RAR / NZ was ordered forward to search and destroy the bunker systems . The North Vietnamese let the Australians advance some into the bunker complex before opening up with everything they had . 11 Platoon , suffered three killed and two wounded . Many grenades thrown by the North Vietnamese fortunately did not explode , reducing casualties . Unfortunately for the Australians this would be fought hand to hand as the Centurion tank s of the 1st Australian Task Force had left Vietnam . 12 Platoon was also pinned down and could not move forward . The bodies of the three killed Australian soldiers could not be pulled back and orders were given to pull back , which under heavy fire did not happen until 16 : 00 . Just as the sun was setting the Australians ran into another enemy force , with the commanding officer of 11 Platoon , Gary McKay being hit twice by a sniper ' s bullet in the shoulder . The bunker system they had come across was found later to be the 33rd Regiment ' s Headquarters . Artillery fire was brought down onto the surrounding area as more North Vietnamese forces joined the battle . The North Vietnamese disengaging at 21 : 00 just as the Australians were running low on ammunition . Aftermath . After a number of hours of fighting the elements of the 33rd Regiment NVA pulled out of the bunker system and moved north after recovering the dead and wounded they could carry . The Australian wounded were evacuated by helicopter in the morning of 22 September . Five Australians had been killed and 30 wounded . Total North Vietnamese losses are unknown , however fourteen bodies were found on the battlefield . The three Australian soldiers left behind were recovered by the New Zealand company of 4 RAR / NZ . For his role in the battle , Second Lieutenant Garry McKay , who was badly wounded , received the Military Cross .