Storming of Indian Batteries at Badli-ki-Serai The advance of the British force towards Delhi was courageously opposed by the Sepoys on 8 June 1857 at Badli-ki-Serai. Heavy losses were incurred by the British force in this action; among the killed was Colonel Chester, Adjutant General of the Army. Advance of the Siege-Train The fortifications of Delhi proved to be too strong for the heavy guns which originally came with the Delhi Field Force. Therefore, a siege-train consisting of nearly fifty pieces of heavy ordnance was brought to Delhi. It was accompanied by innumerable carts, loaded with ammunition, and extended over seven miles. The siege- train arrived in Delhi on 3 September 1857.