(EXPLAINER) Canada Prime Minister Justin Trudeau’s allegation last year that gunmen — acting on behalf of the Indian government — were connected to the assassination of a Sikh separatist leader near Vancouver sent relations between the two nations spiraling.   

A year later, the rift has grown worse. Both countries have expelled diplomats, while Canadian authorities have made arrests and alleged that India Prime Minister Narendra Modi’s government has been involved in a series of violent acts targeting Sikhs across Canada.

But India’s government has denied involvement in the killing of Hardeep Singh Nijjar, a Canadian Sikh involved with the Khalistan movement. The movement’s aim is for the creation of an independent Sikh state.

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At the same time, India has accused Canada of providing a safehaven for Sikh separatists and indulging them for political gain.

Here’s everything you need to know about the growing rift between the two nations:  

Nijjar’s murder and fallout

Last June, Nijjar, 45, a supporter of an independent Sikh homeland known as Khalistan, was killed outside a Sikh cultural center in Surrey, a suburb of Vancouver located south of the Fraser River on the U.S.-Canada border.

Born in India, Nijjar immigrated to Canada in the 1990s. He had been labeled a “terrorist” by New Delhi for supporting the separatist Khalistan movement — which calls for the creation of an independent homeland for Sikhs carved from India’s territory.  

Sikhs are a small religious group with about 25 million around the world, most of them in India. Canada has a Sikh population of more than 770,000 people, equal to about 2% of the country’s total population. In fact, Canadian Sikhs constitute one of the country’s largest non-Christian religious groups and form the country’s largest South Asian ethnic group. 

The vast majority of Sikhs live in Asia, but government figures show that there were 455,000 Sikhs in Canada in 2011 — more than double the 1991 population estimate of 145,000. Almost half of the country’s Sikh’s make British Columbia their home. 

The call for a separate Sikh state began in the wake of the fall of the British Empire. In 1940, the first explicit call for the creation of Khalistan was made in a pamphlet titled “Khalistan.”

Three months later, Trudeau, speaking to the Canadian Parliament, said, “Over the past number of weeks, Canadian security agencies have been actively pursuing credible allegations of a potential link between agents of the government of India and the killing of a Canadian citizen, Hardeep Singh Nijjar.”

Last May, four men were arrested in connection with the assassination. The accused, who allegedly played roles as shooters, drivers and spotters on the day Nijjar was killed, remain in a Canadian jail.

Sikhs feel threatened

The Royal Canadian Mounted Police, the country's national police service, said recently that it has compiled more than a dozen cases involving threats to Sikhs living within its borders.

Protestors gathered last Friday outside the Indian consulate in Toronto. Kuljeet Singh, a spokesperson for Sikhs for Justice, called on Canada to shut the country’s Indian consulates down.

“We believe India remains a threat to Canada's sovereignty, Canada's freedom of speech and Canada’s freedom of expression,” Singh said.

Last week, Canada expelled six Indian diplomats, linking them to Nijjar's murder and part of a larger effort target Sikh dissidents by using mafia-style tactics, such as drive-by shootings and arson. The authorities did not provide details regarding each individual threat.  

Trudeau said Canada had found “clear and compelling evidence that agents of India’s government have engaged in and continue to engage in activities that pose a significant threat to public safety.”

India denies any involvement

Modi’s government, meanwhile, has denied any wrongdoing, calling the allegations “strange” and “ludicrous.” Modi’s government also retaliated by ordering the expulsion of six Canadian diplomats in India.

At the same time, India has accused the Canadian government of being soft on supporters of the Khalistan movement. Indian authorities also said Canada has for decades failed to confront what it calls Sikh militants and failed to extradite them for prosecution.

That doesn’t make the threats any less real. For example, Inderjeet Singh Gosal, a close friend of Nijjar, told The Guardian he received a panicked call from his wife that police warned his life was in danger.

Gosal, who now leads the movement following Nijjar’s murder, said, “When I stepped into this role and over this activism, I knew there was a moment when they’d come after me. It’s never going to stop. But this is what I signed up for. I’m not afraid of death at all.”

Despite their denials, Gosal said, “We know what India is capable of.”

“We’ve seen it for years,” he added. “We have no illusions. We know they have vast resources and no mercy.”

Clemente Lisi is the executive editor of Religion Unplugged. He previously served as deputy head of news at the New York Daily News and a longtime reporter at The New York Post. Follow him on X @ClementeLisi.