The Canadian intelligence establishment is yet to identify any Indian citizen potentially linked to the killing of Hardeep Singh Nijjar flying in or out of Canada, either directly or indirectly, before or after the killing of the wanted Khalistani terrorist in June.

Sources confirmed the investigators, belonging to the local police in Surrey, the Royal Canadian Mounted Police (RCMP) and the Canadian Security Intelligence Service (CSIS), had extensively tried to ascertain if Indian-origin agents travelled in or out of the country around June 18. The exercise didn't yield anything, sources said.

With the Canadian police yet to achieve a breakthrough in its search, it is being suspected that the assailants would have fled the country after the killing.

In Nijjar's killing, the Canadian police had zeroed in on two suspicious vehicles - a burnt car and a silver 2008 Toyota Camry - which was supposedly the getaway vehicle used by the assassins after the murder. This, sources confirmed, was reminiscent of several gang-related killings in the area in the recent past.

Also, as per Washington Post, Nijjar's killers pointed a gun at one of his aides who had tried to give them a chase but did not fire, a restraint characteristic of those who are driven by an intense resolve to settle a personal score but are still strategic enough not to let their vengeance travel so far as to hurt collaterals, a senior intelligence functionary said.

Besides, Nijjar's family has given many statements to the media suggesting he was in close contact with the CSIS, though it is not clear whether he was an informant.

(With inputs from agencies)