The high-profile killing of a Canadian citizen who advocated for an independent Sikh homeland has prompted revelations from fellow activists that police warned them of threats to their own lives in the wake of his death.

Hardeep Singh Nijjar was shot to death in Surrey, B.C., on June 18. Three months later, Prime Minister Justin Trudeau made an explosive allegation when he said Ottawa believed the Indian government had involvement in Nijjar's killing.

India publicly denied any involvement, prompt…