Four VC battalions attempted to advance over a series of bridges into south Saigon, but were blocked by US Army units and eventually forced to retreat with heavy losses.

When the Army of the Republic of Vietnam (ARVN) 33rd and 38th Ranger Battalions left south Saigon on the morning of 6 May to block the VC thrust toward Chợ Lớn in west Saigon, II Field Force, Vietnam commander General John H. Hay arranged for US troops to fill the gap until ARVN units could be found to do the job.

What was intended as a temporary expedient turned into one of the most vicious and sustained battles the Americans would experience in the Saigon area at any point in the war.

The road passed through the Eighth District, a Catholic working-class slum that in recent years had sprouted along the southern edge of the Doi Canal.

The mechanized unit, commanded by Captain Edmund Scarborough, parked its M113 armored personnel carriers (APCs) at two of the three bridges that spanned the Doi Canal.

Scarborough set up his headquarters near the Tung Tien Vuong Bridge (10°44′28″N 106°39′22″E / 10.741°N 106.656°E / 10.741; 106.656), situated approximately three kilometers due south of the Phú Thọ racetrack.

Using the many streams and canals that crisscrossed southern Gia Định Province, the four battalions travelled by foot and sampan right up to the edge of the city without being detected.

A company from the Phu Loi I Battalion, having already crossed the canal on sampans without being detected, also opened fire from the north bank.

The outgunned policemen were on the verge of abandoning the building when several helicopter gunships appeared overhead and their guns forced the VC to seek cover.

An estimated company of VC was getting ready to attack the station from a nearby rice paddy when the four APCs rolled into the compound.

The fight remained hotly contested until an AH-1 Cobra gunship strafed the length of the dike, putting the VC to flight.

[1]: 576 While soldiers from the 506th Battalion continued to snipe at the 1st and 2nd Platoons, the main VC threat shifted to the hamlet of Cầu Mật (10°44′49″N 106°40′48″E / 10.747°N 106.68°E / 10.747; 106.68), which sat on the canal road a few hundred meters to the west.

Many already knew something about urban combat; Company A had fought in the Tet Offensive battle of Cholon and Phu Tho Racetrack.

In the confusing warren of houses and alleyways, there was always a risk that the VC could sneak through the cordon and double back for a surprise rear attack.

[1]: 577 As the battle for Cầu Mật heated up, Hay directed Major general George C. O'Connor to commit more men from his 9th Infantry Division.

The scout platoon from the 2nd Battalion, 47th Infantry Regiment, joined the action a short time later, adding some extra punch with its APCs and .50-caliber machine guns.

In hindsight, the sudden burst of activity was probably designed to draw attention away from the western suburbs where the Cuu Long II Regiment and the 9th Division were trying to withdraw from the Battle of West Saigon.

When Company B, 6/31st Infantry, arrived at DeLuca’s command post early in the afternoon, he ordered them to assist a police facility that had come under attack.

The Marines had enough men to protect the bridge, but not enough to clear Xom Ong Doi, so the 9th Infantry Division extended its zone of responsibility to cover the eastern part of the Eighth District.

It gave the mission of securing Xom Ong Doi to the 6/31st Infantry, commanded by Lt. Col. Joseph H. Schmalhorst, which was currently patrolling the region south of the 5A Bridge.

The advancing Americans came under small arms fire but it was not particularly heavy; the 100 or so living members of the 5th Nha Be Battalion were likely stretched thin across the hamlet.

The mechanized unit sped through downtown Saigon and then crossed over the Tan Thuan Bridge before pulling up along the north side of Xom Ong Doi.

For all intents and purposes, it was a complete encirclement because helicopter gunships from the 7th Squadron, 1st Cavalry, watched the open fields to the east.

Company B responded with a fusillade of machine gun and small arms fire that tore into the flimsy buildings that lined the road.

When the two US battalions pulled back because of darkness, gunships continued to pound Xom Ong Doi by the flickering light of a hundred or more fires.

Despite having abundant gunship and artillery support, DeLuca’s infantry made little progress that day, losing six killed and 40 wounded.

Airstrikes, artillery, and gunships pounded the enemy positions through the night as DeLuca’s men readied themselves for another day of gruelling, close-quarter combat.

Colonel Antila ordered Companies A and C of the 5/60th Infantry, to rescue the besieged government soldiers and trap the VC force.

When Schmalhorst’s troops resumed their advance late that afternoon, they faced only sporadic sniper fire as they moved down the highway.

[1]: 583 This article incorporates public domain material from websites or documents of the United States Army Center of Military History.