Korean axe murder incident - Wikipedia

On August 21, 1976, "Operation Paul Bunyan" begins in retaliation for the "Korean axe murder incident" 3 days prior. 110 troops, 27 helicopters, 3 B-52 bombers are deployed to the Korean Demilitarized Zone to cut down a poplar blocking the view of UN observers. From the article:

"On August 18, 1976, a group of five Korean Service Corps (KSC) personnel escorted by a UNC security team consisting of Captain Arthur Bonifas, his South Korean (ROK) Army counterpart, Captain Kim, the platoon leader of the current platoon in the area (First Lieutenant Mark Barrett), and 11 enlisted personnel, both American and South Korean,[3] went into the JSA to trim the tree.

The two captains did not wear side arms, as members of the Joint Security Area were limited to only five armed officers and 30 armed enlisted personnel at a time. However, there were mattocks in the back of the 2½ ton truck. The KSC workers had the axes they brought to prune the tree branches.

After trimming began, about 15 North Korean soldiers appeared, commanded by Senior Lt. Pak Chul, whom the UNC soldiers had previously nicknamed "Lt. Bulldog" due to a history of confrontations.[4][5] Pak and his subordinates appeared to observe the trimming without concern for approximately 15 minutes, until he abruptly told the UNC to cease the activity, stating that the tree could not be trimmed "because Kim Il Sung personally planted it and nourished it and it's growing under his supervision."[1] Captain Bonifas ordered the detail to continue, and turned his back on Lt. Pak Chul.[6]

Attack
After being ignored by Bonifas, Pak sent a runner across the Bridge of No Return. Within minutes, a North Korean guard truck crossed the bridge and approximately 20 more North Korean guards disembarked carrying crowbars and clubs. Pak again demanded that the tree-trimming stop. When Bonifas again turned his back on him, Pak removed his watch, carefully wrapped it in a handkerchief, placed it in his pocket, and then shouted, "Kill the bastards!"[6][7] Using axes dropped by the tree-trimmers, the KPA forces attacked the two U.S. soldiers, Bonifas and Barrett, and wounded all but one of the UNC guards.[4][8]

While Bonifas was knocked to the ground by Pak and then bludgeoned to death by at least five North Koreans, Barrett jumped over a low wall which led past a 4.5-metre (15 ft) deep tree-filled depression, just across the road from the tree. The depression was not visible from the road because of the dense grass and small trees. The entire fight lasted for only 20 to 30 seconds before the UNC force managed to disperse the North Korean guards and place Bonifas' body in their truck.[7] However, there was no sign of Barrett and the two UNC guards at OP No. 5 could not see him.

The UNC force did, however, observe the North Korean guards at KPA No. 8 (along the UNC emergency egress road) exhibiting strange behavior, in that one guard would take an axe and go down into the depression for a couple of minutes and then come back up and hand the axe to another guard who would repeat the process.[9] This went on for approximately 90 minutes until the UNC guards at OP No. 5 were informed that Barrett was missing, at which time they informed their superiors about the KPA activity in the depression. A search and rescue squad was quickly dispatched and found that Barrett had been attacked with the axe by the North Koreans.[9] Barrett was recovered and transferred to a hospital in Seoul via an aid station at Camp Greaves, but died during the journey.

Captain Shirron (Bonifas' replacement), Captain Shaddix, the joint duty officer's driver, the joint duty officer, and the OP No. 5 guard witnessed the attack from OP No. 5 and recorded the incident with both a black and white camera, which ran out of film, and Shaddix's 35 mm camera with a telephoto lens. The UNC guard at CP No. 3 (Bridge of No Return) recorded the incident with a movie camera."