Marine mortars and artillery and two UH-1E Huey gunships from VMO-6 provided supporting fire and Company I was able to withdraw sustaining only 4 wounded, while the PAVN had lost at least 35 dead.

Under the cover of Marine gunships and artillery fire, the survivors and dead of the isolated squad were brought back into the Company perimeter.

[2]: 139–140 Following their defeat in the Tet Offensive there was a marked decline in PAVN activity along the DMZ apart from ongoing artillery, rocket and mortar fire.

Reinforced by the command group and a rifle platoon from Company H, the patrol engaged the PAVN with small arms and 81mm mortars.

[2]: 357 On 7 July, to exploit the results of Operation Thor in the Cửa Việt-Dong Ha sector, the 9th Marines began a sweep of the area between Con Thien and the DMZ.

On 11 July, 4 km northeast of Con Thien, elements of 3/9 Marines discovered a reinforced PAVN platoon in the open.

The PAVN again broke and ran, and Company F moved through the area, capturing a number of weapons and counting 11 dead.

[2]: 387 On 15 August, a PAVN company attacked a four-man Marine reconnaissance team southeast of Con Thien near the abandoned airstrip at Nam Đông.

Within minutes a platoon from Company A, 1st Marines, accompanied by three tanks, moved out of positions 1 km away and headed south to assist.

[2]: 389 As PAVN activity continued to increase in the eastern DMZ, particularly north of Con Thien, the Marines decided to act.

Of special interest were repeated sightings of low, slow moving lights during hours of darkness which, it was assumed, came from enemy helicopters thought to be resupplying forward positions with high priority cargo such as ammunition and medical supplies or conducting medevacs.

On 19 August, after 60 Arclight strikes 2nd Battalion, 1st Marines assaulted into three landing zones in the Trung Son region of the southern DMZ, 5 km north of Con Thien.

6 km southwest of Con Thien Mike Company, 3/9 Marines intercepted a reinforced PAVN platoon, under the cover of airstrikes and artillery they kill 30 NVA and captured 2.

[2]: 389 On 24 August at 17:00, Marine reconnaissance team Tender Rancho was moving 7 km southeast of Con Thien near Dao Xuyen, when it surprised a group of 15 bivouacked PAVN troops killing 6.

During the remainder of the 25th and into the 26th, as Companies C and D, 1st Marines pushed southward toward the other blocking forces, the PAVN made several unsuccessful attempts to break the cordon.

[2]: 389–390 On 31 August 1st Marines was relieved of responsibility for the Kentucky area of operations by the Army's 1st Brigade, 5th Infantry Division (Mechanized).

[2]: 392 On 13 September following Arclight and naval and land artillery strikes 3 Brigade task forces from the 5th Infantry Division attacked into the DMZ northeast of Con Thien.

To the east the 1st Squadron, 7th ARVN Armored Cavalry, supported by two platoons from Company A, 3rd Tank Battalion, simultaneously attacked to the north and northeast of A-2 and Gio Linh.

Following in the wake of the tanks, and supported by helicopter gunships, the ARVN infantry killed an additional 68 PAVN and captured one.

On the left flank, after encountering mines and antitank fire, the three Army task forces joined the action, accounting for another 35 PAVN and seizing a large cache of mortar rounds.

The allied forces reached their northernmost objectives, turned south, and returned to their bases by late afternoon.

In coordination with the ARVN 2nd and 3rd Battalions, 2nd Regiment, and the 3rd Marines, the companies moved to a position west of Con Thien and then attacked north across the southern boundary of the DMZ, toward the Dong Be Lao mountain complex.

[2]: 394 Despite heavy rain during October, ground and aerial reconnaissance missions indicated the presence of a sizable PAVN force south of the Ben Hai River between Gio Linh and Con Thien.

On 23 October the brigade task force, composed of three companies of the dismounted 1st Battalion, 61st Infantry attacked north from A-3 and Con Thien into the DMZ and then eastward along the Ben Hai River toward the ARVN 2nd Regiment and Company H, 9th Marines which had earlier trapped a PAVN force killing 112.

While ground reconnaissance would be a part of the effort, attended and unattended detection devices or sensors would provide a majority of the surveillance capability.

As part of the implementation of Duel Blade the "A" and "C" strongpoint sites considered essential would be used as fire support bases, while those of no value, such as A-3 and C-3, would be closed.

[2]: 449 On 10 February at 17:45 a U.S. observation aircraft received fire over the DMZ 4 miles (6.4 km) north of Gio Linh and 400m south of the Bến Hải River.

This article incorporates public domain material from websites or documents of the United States Marine Corps.