Passage: In November 1825, the Burmese decided to throw everything they had into a last-ditch effort. Starting in mid-November, the Burmese forces, consisting mainly of Shan regiments led by their sawbwas, threatened Prome in a daring circular movement that almost surrounded the town and cut off communications lines to Yangon. In the end, the superior firepower of the British guns and missiles won out. On 1 December, Gen. Campbell, with 2500 European and 1500 Indian sepoys, supported by a flotilla of gunboats, attacked the main Burmese position outside Prome. On 2 December, Maha Ne Myo was killed by a shell launched from the flotilla. After Maha Ne Myo's death, the British dislodged the Burmese by 5 December.The defeat in Prome effectively left the Burmese army in disarray. The Burmese army was in constant retreat from then on. On 26 December, they sent a flag of truce to the British camp. Negotiations having commenced, the Burmese were forced to accept the British terms to end the war, signing the Treaty of Yandabo in February 1826.

Question: What kind of flag was sent on 26 December?
flag of truce