"After Guru Arjun Deva had been tortured and done to death by Jahangir, he [Ahmad Sirhindi] wrote in letter No. 193 that “the execution of the accursed kafir of Gobindwal is an important achievement and is the cause of the great defeat of the Hindus.”"
January 1, 1970
https://en.wikiquote.org/wiki/Guru_Arjan