Tense relations between India and Canada hit a new low this week, as both countries expelled each other’s top diplomatic officials.

The move came after RCMP officers alleged Indian government agents were involved with homicides, extortions and other violent criminal activities in Canada.

It’s the latest development in an escalating dispute over the June, 2023, killing of Sikh activist Hardeep Singh Nijjar. The intensifying diplomatic storm has seen both countries withdraw their respective ambassadors and top diplomatic staff, with India flatly denying allegations it uses mobsters to target Sikh separatists in Canada.

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What started the heightened diplomatic tensions between India and Canada?

Hardeep Singh Nijjar was fatally shot in his pickup truck in June, 2023, after he left the Sikh temple he led in the city of Surrey, B.C. An Indian-born citizen of Canada, he owned a plumbing business and was a leader in the Khalistan movement, which seeks to create an independent Sikh homeland in regions of Northern India. The organization is termed anti-national, and banned in India.

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Prime Minister Justin Trudeau said in September, 2023, there were credible allegations that India’s government had links to the killing. India denied the allegations at the time but said Mr. Nijjar was involved in “terrorism.”

Canada expelled an Indian diplomat over the dispute, and in response India expelled a Canadian diplomat and froze consular services for Canadians for nearly two months.

Tensions boiled over again in May, 2024, when Canadian police said they had arrested three Indian nationals accused of involvement in Mr. Nijjar’s killing and were “investigating if there are any ties to the government of India.” India rejected the allegations, saying Canada had a “political compulsion” to blame India.

What are the latest developments in Canada and India’s diplomatic dispute?

Now, Canada says that India’s top diplomat in the country is a person of interest in the killing, and police have uncovered evidence of an intensifying campaign against Canadian citizens by agents of the Indian government.

The RCMP said it had credible evidence of the involvement of Indian agents “in serious criminal activity in Canada,” including links “to homicides and violent acts” and interference in Canada’s democratic processes, among other things.

Meanwhile, Foreign Affairs Minister Mélanie Joly tied Indian officials to Nijjar’s assassination and said Canada had gathered “ample, clear and concrete evidence which identified six individuals as persons of interest in the Nijjar case.”

Who was Hardeep Singh Nijjar?

Mr. Nijjar was the 45-year-old president of the Guru Nanak Gurdwara in Surrey, B.C.

He had arrived in Canada from India in the 1990s and later became a Canadian citizen. In British Columbia, he was known as a plumber as well as a prayer leader and an outspoken advocate of the Khalistan movement that has championed Sikh separatism since the 1970s.

On June 18, 2023, Mr. Nijjar was killed when two masked men gunned him down as he sat in a Dodge Ram outside the temple.

In the weeks before his death Mr. Nijjar had already told associates that he had received cryptic warnings from Canadian Security Intelligence Service officers that someone was coming to harm him.

What are the roots of the Khalistani movement in Canada?

A flareup in tensions between the government of India and Sikh separatists in the 1970s and 1980s led to outbreaks of violence.

During the height of the insurgency in 1984, Indian prime minister Indira Gandhi ordered her soldiers to stop Sikh militants by storming the Golden Temple in Amritsar, considered Sikhism’s holiest shrine. In retribution, Ms. Gandhi was assassinated a few months later by her own bodyguards. News of her killing ignited deadly pogroms directed at Sikhs all across India.

Shortly after, the separatist Sikh factions made a declaration for an independent state of Khalistan, an idea that has since been championed by some Sikhs, including many living within Canada’s 770,000-strong diaspora community.

The separatist movement proposes that such a country could be partitioned from territory comprising the current Indian state of Punjab – a jurisdiction that is nearly 60-per-cent Sikh.

Elsewhere, India is a country dominated by Hindus, who also represent a strong minority in Punjab state.

Mr. Nijjar was among those pushing an unofficial referendum among the Sikh diaspora in Canada, Europe and Australia to press for an independent Khalistan in present-day India.

Who is Lawrence Bishnoi, and what is his Canadian connection?

The RCMP accused Indian government agents of being linked to an organized crime group called the “Bishnoi group”.

India’s top investigative body, the National Investigation Agency, describes the group as a criminal gang headed by Lawrence Bishnoi, whose lawyer says he contests more than 40 cases accusing him of crimes such as murder and extortion, with many trials yet to begin.

Mr. Bishnoi is a 31-year-old law graduate, in jail since 2015, of running a transnational crime syndicate.

In statements, the NIA has said he runs his syndicate from jails in different states, as well as countries such as Canada, through associates, who have been in contact with “pro-Khalistani” elements in neighbouring Nepal and other countries.

Canada has not stated specific charges, but the RCMP said there was “specific targeting” of those supporting Khalistan in the country.

It named the Bishnoi organized crime group as having earlier claimed some of those actions, and accused it of being linked to Indian agents.

How are the U.S. and U.K. reacting to the dispute?

Both the United States and Britain urged India to take allegations its officials are involved in violent crimes in Canada seriously and co-operate with the Canadian probes, as political parties in Ottawa took steps to launch an emergency parliamentary study of the controversy.

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On Tuesday, an Indian inquiry committee met with U.S. officials on another investigation, into U.S. accusations that an Indian intelligence official was involved in a foiled plot to assassinate another Sikh separatist, dual U.S.-Canadian citizen Gurpatwant Singh Pannun, in New York. The Indian official, whom U.S. authorities have not named, is accused in a Department of Justice indictment of working with an alleged international drug and gun trafficker named Nikhil Gupta to arrange a murder-for-hire of Mr. Pannun.

Separately, the British government released a statement, saying “we are in contact with our Canadian partners about the serious developments outlined in the independent investigations in Canada. The U.K. has full confidence in Canada’s judicial system.”

Will the dispute affect the South Asian diaspora community, and Indian citizens studying or working in Canada?

As tensions escalate, some in the Indian diaspora say they’re concerned about how the situation might affect travel between India and Canada, especially if the conflict escalates to visa suspensions.

In September of last year, India temporarily suspended visa services for Canadian citizens after Canada said there were “credible allegations” of Indian involvement in the killing of Mr. Nijjar.

India’s Ministry of External Affairs has not announced any similar measures this time, but has said they “reserve the right to take further steps in response to the Trudeau Government’s support for extremism, violence and separatism against India.”

For Indian citizens already in Canada applying for work permits and permanent residence, the rising tensions shouldn’t affect processing times, experts say.

In-Canada processing times shouldn’t be affected, though individuals applying from India could possibly see longer processing times, GTA-based immigration consultants Kubeir Kamal and Sahil Sayal said in a video discussion posted on social media.

Will trade between Canada and India be affected?

The diplomatic row could derail a trading relationship that already underperforms its potential, experts warn.

International Trade Minister Mary Ng tried to reassure Canadian businesses, issuing a statement acknowledging the “uncertainty” the situation has created for exporters and investors. She said the federal government will continue to support commercial and economic ties between the countries.

But analysts say there is no way the trading relationship between Canada and India, the world’s fastest-growing economy, can escape unscathed from this latest escalation in tensions – at least not in the immediate future.

“This is an extremely significant development. We are seeing a diplomatic disruption, a rupture in the relationship, on a scale that is unprecedented,” said Vina Nadjibulla, vice-president of research and strategy for the Asia Pacific Foundation of Canada.

What are Canada’s politicians saying about the diplomatic spat with India?

On Tuesday, the NDP’s call for the House of Commons public-safety committee to launch an emergency study of police allegations against the Indian government agents was unanimously agreed to by all members of parliament.

Earlier, in his news conference on Thanksgiving Monday, Mr. Trudeau said the police pre-emptively released the allegations against India in an effort to “disrupt the pattern of Indian diplomats” collecting information on Canadians through “questionable and illegal means.”

Mr. Trudeau alleged that information was then fed to criminal organizations, which subsequently committed violent crimes, including killing and extortion.

“We will never tolerate the involvement of a foreign government threatening and killing Canadian citizens on Canadian soil – a deeply unacceptable violation of Canada’s sovereignty and of international law,” the Prime Minister said.

How are news outlets in India covering the diplomatic dispute?

Indian news publications such as The Times of India and NDTV have largely chosen to brand the dispute as a ‘major win’ for the Indian narrative.

By choosing to quote expert sources critical of Mr. Trudeau, such as Canadian journalist Daniel Bordman, the outlets have taken a pro-India editorial slant, that is evident in their headlines, such as the following:

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What does the way forward look like for India and Canada?

Experts say the standoff will make it difficult for both countries to move forward with a once-promising partnership, and could impact India’s ambitions as it tries to project itself as a rising world power.

“India-Canada bilateral relations, which have been on a downslide since last year, will take a further hit, which will take a long time to repair,” said Praveen Donthi, senior analyst with the International Crisis Group.

New Delhi’s anxieties about Sikh separatist groups have long been a strain on its relationship with Canada, where some 2 per cent of the population is Sikh. India has increasingly accused Prime Minister Trudeau’s government of giving free rein to Sikh separatists from a once-strong movement for the creation of Khalistan.

Mr. Donthi said the growing rift between India and Canada will also “impact the growing strategic understanding between the U.S. and Western democracies” that are wooing New Delhi as a counterweight to Beijing.

“The Canadian allegations against India come against the grain, as New Delhi has been enjoying a favourable external environment,” Mr. Donthi said. “This will throw a spanner in the works for India’s great power ambitions.”

With files from the Globe’s Ottawa Bureau, The Associated Press and Reuters.