Four days later other South Vietnamese troops drove 16 kilometers into Cambodian territory.
They'd also set up bases on Cambodian territory from which attacks were launched against South Vietnam.
France was also permitted to maintain military bases on Cambodian territory.
In fact, until 2003 access from Cambodian territory was possible only via a gruelling hike through jungle and mountains.
Thai forces have denied they are inside Cambodian territory.
Then the bad set in, from the 13th century, as ascendant neighbours steadily chipped away at Cambodian territory.
If the plane should be downed in Cambodian territory, it would appear to be Vietnamese.
Several women at Site 2, where 140,000 people live within a mile of Cambodian territory, described sexual assaults by rangers.
"We have 85 percent of the Cambodian territory in population," he said.
During this time, Vietnamese forces made extensive use of Cambodian territory to transport weapons, supplies, and troops.