Air operations The Battle of Lak Sao, fought between November 1963 and January 1964, was a major engagement of the Laotian Civil War.

Although unsupported in this proxy action by his backers in the U.S. Embassy, he went ahead with his plan to push northwards from Nhommarath, then veer eastwards to the Vietnamese border.

In a move to assert control over Laotian territory, he authorized military operations in northwestern Laos near the Chinese, Burmese, and Vietnamese borders.

The North Vietnamese government would not honor the treaty, however; they withdrew only a token contingent, leaving most of their invading troops inside Laos.

After advancing northward up Route 8 to Lak Sao, the RLA/FAN forces would turn northeast towards the Nape Pass, an entry point to the Democratic Republic of Vietnam.

[5] The thrust from Lak Sao moved toward Nape Pass as planned in early December, rolling down a road freshly improved by the North Vietnamese, and brushed off a blocking attempt by a company of Pathet Lao guerrillas.

This was a prelude to an aggressive resistance that began on 15 December, as the North Vietnamese committed a minimum of three battalions to confront the Laotian thrust.

While sending one column down Route 8 to hit the Laotian task-force head-on, the North Vietnamese also circled around southwards through the Mu Gia Pass to strike towards Nhommarat.

When Khamkeut came under mortar fire from the PAVN pursuers, 11 BP evaded an additional 6 kilometres (3.7 mi) west to the Nam Theun riverbank.

After a second drop the following morning, the two paratroop battalions bypassed Khamkeut to relieve the garrison still holding their ground at Lak Sao.