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CENTRAL INTELLIGENCE AGENCY Office or Current Intelligence5
SUBJECT: Ciiincse Communist Military Presence in North Vietnam'
The Chinese Communists in5 beganimited number of military support units into North Vietnam (DRV). This marked the first time that Chinese troop units had been stationed outside Chinahen Peking withdrew the lasts troops from North Korea. Unlike the Chinese troops in Korea however, the units detected in North Vietnam thus far have been restrictedewsupport units and probably some local security forces, including antiaircraft artillery.
These Chinese forces for the most part havo been moved from adjacent areas of south China into the northeast regione
On the basis of tentative information,
however, we estimate tbat there may00 Chinese military personnel now in North Vietnam;
aerial photography has revealedin the northeast DRV that is probablyto tbe presence of Chinese support units.sector of the Hanoi-Pinghsiang rail lineimproved and several new truck parks haveup in the border area, probably to facilitate
This memorandum has the concurrence of the Director, DIA.
the increased flow of supplies into North Vietnam.
4. Although there is no firm evidence that any additional Chinese military units have deployed into North Vietnam since August, there are signs that several units, probably railway engineer and/ or conventional engineer units, may be preparing to do so in tho near future. These unite, which began to appear near the Vietnam border in mid-September, are either newly formed or taken from areas of China other than the immediate border area. At least one railway engineer unit has movedosition where it can deploy rapidly into theDRV, where the Hanoi-Kunming rail line has been subjected to frequent bombing since mid-July.
Thore is no evidence that the deployment of logistic support units to the DRV hasuildup of Chinese combat forces in the Sino-DRV border area. uildup would probably precede any major deployment of Chinese combat units into North Vietnam. There are however, tentative
Inave been cade lor I! introduction o:
orce of considerable size into the border area. Thus available intelligence suggests that the Chinese are taking some of the necessary steps to irove pore units rapidly into Vietnam should the
North Vietnam is significantly ex-
war escalate. On the basis of tholr practice to lOIMSIMIbKlMSYri
date, we expect to receive some earlyI hinese
involvomont in pandod.
The first Chinese unit detected in North Vietnam appeared in the northeast coastal area Tlon Yon in mid-Juni
12. Chinese railway engineer units are highly specialized unitsroven capability for rapid construction and repair of rail lines. Byugust, photography revealed some newwork on the northern part of the Hanoi-Ping-hsiang railroad.
construction appears to involve efforts tothe capacity and efficiency of this important narrow gauge line, by eliminating sharp curves and steep gradionts. Those improvements are apparently being accomplished inanner as to minimize the disruption of rail traffic between China and the DRV.
photographyshowed a rs
high level" of truck activT^^uncTgseTerai apparently
newly established vehicle storage areas stretching
from Pinghsiang, China, to Langson in North Vietnam.
TOP SECRET TRINE
reported aitor the iriJTo that they nan encounterod unusually heavy flak; two US aircraft were downed by ground fire.
IS. To sun up, at least live, and possibly one or two rore, Chinese nilitary units have -iow Scon detected roving into North Vietnam. Thest units appear toossible AAAuspect border/coastal security dofense division, elementsailway enginoorotor transport regiment, and another possible security unit of at least regimental size. At normal organizational strengths, this would nmount to0 troops ln all. There ore prohably also sone headquarters and service personnel.
New Chinese Construction Units Sear DRV Bon ir
1). Although no Chinese nilitary units rave "jecn detected Moving into North Vietnam since tuere are indications that several new Chinese construction units cay so assembling near the DRV border lor possible deployment into the country.Original document.