Sardar Chatar Singh, a BrarJatt, was, according to Sarup Singh Kaushish, Guru Kian Sakhain, a Sikh spy who, during the siege of Anandpur by the hill rajas in September October 1700, used to mix with the enemy and bring intelligence about their strength, dispositions and plans. It was he who carried to Guru Gobind Singh the news one evening how Raja Kesarl Chand, one of the besieging chieftains, had planned to smash the gate of the Lohgarh Fort on the following morning with the help of a drunken war-elephant.
Reference:-
- adam, Piara Singh, and Giani Garja Singh, eds., Guru kian Sakhian. Patiala, 1986