On a summer evening in June, Sikh leader Hardeep Singh Nijjar was shot dead outside a Sikh temple in British Columbia by two masked gunmen.

Now Canada's prime minister says he suspects India is behind the assassination. This is because Canadian intelligence has identified a credible link between his death and the Indian state, writes the BBC.

"Any involvement of a foreign government in the killing of a Canadian citizen on Canadian soil is an unacceptable violation of our sovereignty," Justin Trudeau said at the recent G20 summit.

Caused great tensions

Nijjar was a prominent voice in Sikhism in the Canadian province and advocated a separate Khalistani state.

In the past, supporters of his have said he was a target of intimidation because of his activism.

His murder has outraged many of his supporters and caused major tensions between Sikh separatists and the Indian government.

Hundreds of Sikh separatists took to the streets of Toronto, along with other cities such as London, Melbourne and San Francisco to protest against the Indian government that they believe is responsible for his death.

India has denied all allegations, calling them "unfounded".