China and the First Indo-China War,1950-54 93 operations and destroy a few small enemy strongholds.This would allow the Vietnamese to gain experience,stimulate and consolidate the momentum of their soldiers,and win the initiative,so that they would be ready for large-scale operations.Then they would start an offensive against Cao Bang,a small town on the Vietnamese-Chinese border,by adopting a strategy of"besieging the enemy to annihilate its relief force":instead of attacking the town directly,they would surround it and sweep out enemy strongholds in the peripheral areas one by one while at the same time attracting and destroying the enemy's reinforcements from Lang Son,and then seize Cao Bang. Chen believed that this strategy would guarantee the occupation of Cao Bang,"thus thoroughly changing the balance of power between the enemy and us in north-eastern and northern Vietnam."The CMCC approved Chen's plan in a telegram to him on 26 July.29 To guarantee that the strategy would be fully followed by Vietnamese units,Chinese military advisers were sent to the battalion,regiment and division levels of Vietnamese troops,with the approval of Ho. The Chinese also offered assistance in military equipment and other war materials to support the border campaign.In late March 1950,Luo Guibo asked the CCP Central Committee for military equipment,ammunition and communication equipment for 16,000 soldiers,to be used in military operations against Cao Bang and Lao Cai.30 From April to September 1950 the Chinese delivered more than 14,000 guns,1,700 machine guns,about 150 pieces of different types of cannons,2,800 tons of grain,and large amounts of ammunition, medicine,uniforms and communication equipment.31 The border campaign started on 16 September.After 48 hours of fierce fighting Vietnamese troops seized Dong Khe,a strategically important spot on Route Colonial Four which linked Cao Bang with the inner land of Vietnam,in the early morning of 18 September.The French command was surprised and dispatched a mobile army corps to Dong Khe while sending five battalions to attack Thai Nguyen,the location of the Viet Minh centre.Chen judged that their real purpose was to rescue their isolated units in Cao Bang.Instead of withdrawing troops from the Dong Khe-Cao Bang area to defend the Viet Minh centre,he strengthened pressure over Cao Bang.On 3 October,as he had predicted,French troops retreated from the Dong Khe and Cao Bang area and moved south,to fall into his trap in nearby mountains. In response to Chen's report about the situation,Mao sent him a telegram on 6 October to give him clear instructions on the final stage of the campaign: It is correct for you to plan first to concentrate your main forces on eliminating the enemy troops south-west of Dong Khe who have now been surrounded by us and then,according to the situation,surround and 29.Contemporary Chinese Army,pp.522-23. 30.The CMAG in Vietnam,p.44. 31.Ibid.pp.44-46;Mu Xin,General Chen Geng,pp.590-93