Sri Guru Gobind Singh Ji and a small number of Sikhs were defending their position in Lohgarh fort of Anandpur Sahib, which was under attack by numerically far suprior forces under the rule of the Moghul Emperor Aurangzeb and the Hindu rulers of the Hill States. Despite superior numbers, the besiedging forces were unable to penetrate the heavily-defended fort. They brought forth an armoured, druken elephant to batter in the gates. Bhai Bachittar Singh was tasked with stopping the elephant, armed with a nagni barcha, a type of spear with a twisted head. Singh Sahib rode out of the fort on horseback and attacked the elephant, thrusting his spear into the animal's forehead and cutting the its trunk with his sword. The wounded elephant retreated, disrupting the attackers' ranks.
Bachittar Singh also took part in actions at Nirmohgarh and Basali and was wounded after taking part in the fifth and last battle of Anandpur. The city was evacuated, and Bhai Sahib safely crossed the Sirsa River. However, he was wounded in a skirmish near Malikpur Ranghran.
Hearing that Nihang Khan was sheltering some Sikhs, the Mughal troops searched his house while the mortally wounded Bachittar Singh lay in a small room attended by Nihang Khan's daughter. Living up to his name, Nihang Khan maintained his cool and succeeded in keeping the search party from entering the room by telling them that his daughter was nursing her very sick husband. Thus the danger was averted, but the life of Bachchittar Singh could not be saved. He succumbed to his injuries and breathed his last on 8 December 1705. Nihang Khan had the cremation performed secretly the following night.