Assessing that with just two infantry battalions 1 ATF did not have the strength to destroy the Viet Cong forces then in Phuoc Tuy, Warr favoured cordon and search operations to eliminate cadres and block the supply of rice from the villages.

In the following months 5 RAR continued to develop cordon and search procedures as 1 ATF attempted to extend its influence, with such operations proving significant in weakening the Viet Cong infrastructure and removing a number of villages from their control.

However, the Australians were convinced that deliberate patrolling techniques were more effective in separating the Viet Cong from the population in the villages while working towards slowly extending government control, and such urgings went largely unheeded.

[11] The results of this operation were modest, and the Australians suffered a number of casualties from a misplaced fire mission from the 161st Battery, Royal New Zealand Artillery which killed four and wounded 13, including Warrant Officer Class Two Jack Kirby, who had earlier received the Distinguished Conduct Medal for his actions at Long Tan, and was among the dead.

[15] Meanwhile, People's Army of Vietnam (PAVN) units operating in the province in early-1967 included Main Forces from the 5th Division, which consisted of the 274th and 275th Regiments, each of three infantry battalions under the command of Senior Colonel Nguyen The Truyen.

Shortly after 05:00 Gilham advised that the Viet Cong—now estimated at two companies—had occupied Lang Phuoc Hai and had subsequently entered the nearby hamlet of Lo Gom, and were attempting to collect boats in order to withdraw from the area by sea.

However, supported by American airstrikes and artillery, the South Vietnamese successfully fought their way out, and by 10:10 the Viet Cong were reported to have withdrawn north-east to the clear rainforest strip known to the Australians as the "Light Green", after suffering heavy casualties during five hours of fighting.

[23][24][Note 1] Two hours later, a Viet Cong company was reported to have formed a tight perimeter in the jungle 2 kilometres (1.2 mi) north of Lang Phuoc Hai, near the abandoned hamlet of Ap My An.

[12] The plan envisioned C Company, under the command of Major Brian McFarlane, being inserted by M113 APCs from A Squadron, 3rd Cavalry Regiment to secure a helicopter landing zone—known as LZ Amber—3 kilometres (1.9 mi) east of Hoi My, just north of the hamlet of Ap My An.

[31] Yet the initial lack of artillery cover had slowed the movement of the 35-vehicle column, while the continual need to reduce speed while traversing the numerous paddy bunds en route was not appreciated beforehand and further hampered their progress.

[34][35] Pinned down and in trouble, Ackland realised that he was facing a sizable and well dug-in force and he attempted to move his sections into an all-round defensive perimeter in order to defend against any counter-attack; the Viet Cong did not attack however and instead remained in their pits.

[36] Under heavy fire from what appeared to be a Viet Cong base area, O'Brien extricated his platoons with difficulty and subsequently broke contact, withdrawing 250 metres (270 yd) with the wounded to the southern edge of the landing zone.

[24] Even as the company was shaking out they were engaged sporadically by a group of Viet Cong just 50 metres (55 yd) to their front, with one Australian soldier being hit before the attack began and later dying at the landing zone before he could be evacuated.

[44] With both A and B Company now heavily engaged, Townsend subsequently asked Murphy whether his APCs could move around to the right in another attempt to outflank the Viet Cong; however, a creek made the ground in that area too boggy for the vehicles and this proved impractical.

However, three previously undetected Viet Cong machine-guns subsequently engaged 5 Platoon, which succeeded in breaking up the Australian attack on the right flank with intense enfilade fire which killed three men and wounded five more.

[48] Surrounded by Viet Cong machine-guns and receiving fire from all sides, the lead Australian elements from B Company could advance no further against a determined and well dug-in force, and all attempts to regain momentum were unable to dislodge the defenders.

[51] However, due to earlier warnings that the Viet Cong were preparing to attack Nui Dat that evening, prior to the start of the operation Graham had ordered Townsend to return to base that afternoon, and this restriction remained extant.

Yet even while the Viet Cong continued to heavily engage both A and B Companies, the remainder of the Australian battalion and the APCs were beginning to line up on the landing zone in preparation for returning to Nui Dat.

[53] Meanwhile, due to the threat posed by the Viet Cong anti-tank weapons the remainder of 2 Troop then arrived under the command Second Lieutenant David Watts to provide added protection; in total 12 vehicles.

[24] The Viet Cong subsequently launched two successive counter-attacks, assaulting B Company from the east and south-east; however, both attacks were repulsed by the Australians, as they responded with small arms fire while Mackay called-in an airstrike.

[12][54] Meanwhile, under covering fire from the APCs of 2 Troop, B Company boarded the remaining carriers, moving into a night harbour near the landing zone with the remainder of the battalion at 19:25, as the last of their casualties were extracted by helicopter.

[54] Meanwhile, a large American force of over 100 armoured vehicles from the 2nd Battalion, US 47th Mechanised Infantry Regiment, supported by a battery of self-propelled guns and helicopters from the US 9th Division, attempted to cut-off likely Viet Cong escape routes.

[24] During the sweep one of the missing Australians—Lance Corporal Vic Otway—was unexpectedly found alive, having spent the night in close proximity to the Viet Cong after being wounded in both legs and falling just metres from the machine-gun he had been assaulting.

[67][68] Although signs of heavy foot traffic were obvious the Viet Cong had long since left the area, while no evidence of blood trails or discarded equipment were found, indicating an orderly retirement from the battlefield.

[69] Further misjudgement and circumstance affected the Australian response once the battle began, with the initial reports that the Viet Cong position was a 'camp' proving incorrect, as had the belief that the dense scrub made the area unsuitable for cavalry.

Yet such lessons still had not been fully grasped by Australian Army training doctrine, and under pressure from Townsend to press on with the attack Mackay had given the order to fix bayonets and charge due to the proximity of his forward platoons to the Viet Cong.

Several days after the battle uncorroborated information was received which suggested that in so doing, the Australians may have also avoided a large area ambush on Route 44 between Hoi My and Lang Phuoc Hai by up to two main force battalions, with the convoy perhaps passing within 200 metres (220 yd) of the Viet Cong command group without realising it.

[72] By inserting into LZ Amber it was probable that 6 RAR had unknowingly also avoided this ambush, yet had subsequently clashed with a large group of Viet Cong resting in the dense jungle adjacent to the landing zone.

The results of the fighting continued to be debated long after its conclusion, and while Graham felt that 6 RAR had inflicted severe casualties on the Viet Cong and that the battle later had far reaching effects on the insurgency in Phuoc Tuy province, Vincent believed that any success had only been marginal at best.

[81] Such losses underscored the need for a third battalion and the requirement for tanks to support the infantry; a realisation which challenged the conventional wisdom of Australian counter-revolutionary warfare doctrine which had previously allotted only a minor role to armour.