This was first breached by the artillery, and then carried by assault by the 53rd and 90th regiments, and a detachment of Sikhs; the latter, single handed, storming another building called the Observatory, in the rear of the Mess House.
At the same time the garrison of the Residency had, in accordance with the plan brought out by Kavanagh, begun operations on their side.

The capture of the Secunderbagh and Mosque had been signalled to them, and while the attack on the Mess House was being carried out they had blown down the outer wall of their defences, shelled the ground beyond, and then advanced, carrying two large buildings facing them at the point of the bayonet.
All day the fighting continued, the British gaining ground on either side.

The next day the houses still intervening between them were captured, and in the afternoon the defenders of the Residency and the relieving force joined hands.

The total loss of the latter was 122 officers and men killed and 345 wounded.
Frank Mallett's letter to Sir John Greendale was not sent off.

He received a bullet through the left arm as the troops advanced against the Secunderbagh, but, using his sash as a sling, led on his company against the defenders crowded in the garden, and took part in the desperate fighting.