received reinforcements and the British readied their defences in Gnathong, a plateau some three or four miles north of Lingtu. On 21May the Lieutenant-Governor of Bengal arrived at Gnathong and the Tibetans attacked the British defences the next day at 7 AM with 3,000 men (British claim). The fighting lasted until 10 a.m. when the Tibetans retreated. The British admitted three killed and eight wounded and claimed to have killed around a hundred Tibetans. The Tibetans retreated back across the Jelap La and no other combat took place, so in June the British started to send some of the troops back to Darjeeling. Renewed operations Towards the end of July, as the British withdrawal continued, renewed Tibetan activity was observed on the other side of the border. The Tibetans were fortifying the mountain passes above the Chumbi valley. Colonel Graham had at his disposition only 500 men plus a garrison at Gnathong, while the Bengal government estimated the Tibetan strength between Rinchingong and Kophu at 7,000, plus a reserve at Lingamathang of 1,000 soldiers. Quickly the Bengal authorities sent reinforcements and by the end of August, Graham's forces at Gnathong had risen to 1,691 soldiers and four guns. After some skirmishes, the Tibetans crossed the Tuko La pass some two miles from Gnathong. Quickly they started building a wall on the ridge of the pass, some three or four feet high and almost four miles wide. Colonel Graham attacked the Tibetan positions around 8 a.m. with three columns. He led the left column, which attacked the blockhouse that guarded the Tuko La pass. Lieutenant-Colonel Bromhead commanded the centre column that was to advance up the main road to Tuko La. The right column, commanded by Major Craigie-Halkett, was to occupy the saddle-back north east of Woodcock hill and hold the Tibetans' left. Around 9:30 am the attack was opened with the bombardment of the Tibetan left flank by the artillery of the British right. At 10:30 the other two British columns were in contact with the Tibetans, and the British penetrated the defences and captured the Tuko La pass, after which the Tibetans retreated through the Nim La pass. After securing his flanks, Colonel Graham moved to attack the Tibetans at the Jelep La pass which was attacked at 2:00 pm and captured shortly afterwards. The next day the pursuit continued and by 4:00 pm the British had occupied Rinchingong.