Canadian police are on the verge of arresting two men who allegedly shot dead a prominent Sikh separatist leader in British Columbia in June, the country’s leading newspaper reported.

The pair is under police surveillance and is expected to be arrested by the Royal Canadian Mounted Police within weeks, The Globe and Mail reported, quoting unnamed sources.

Forty-five-year-old Hardeep Singh Nijjar was leaving a Sikh temple in the Vancouver suburb of Surrey on June 18 when he was shot multiple times in a gangland-style slaying.

The police will explain the alleged assassins’ involvement and that of the Indian government when charges are laid against the two men, The Globe said adding it was not identifying the sources because they were not authorised to discuss national security and police matters.

In September, Prime Minister Justin Trudeau accused the government of India of being behind the shooting of Nijjar, a Canadian citizen who was born in Punjab, and said it was an unacceptable violation of Canadian sovereignty.

The Indian government labelled the bombshell allegation “absurd.” India has criticised Canada for years over giving free rein to Sikh separatists, including Nijjar. Canada has a Sikh population of more than 770,000 representing around 2 per cent of its total population.

Trudeau’s accusation made in Parliament has sent Indo-Canadian relations into a deep freeze. Ottawa expelled a top Indian diplomat and shelved free-trade talks while New Delhi stripped 41 Canadian diplomats of their diplomatic protection and suspended visa services. The visa services have since been restored but bilateral relations remain strained over New Delhi’s worries about the activities of Sikh separatist groups in Canada.

New Delhi had accused Nijjar, a self-proclaimed Sikh nationalist, of being a terrorist. A 2020 statement by the Indian government alleged he was “actively involved in operationalising, networking, training and financing” members of the militant group Khalistan Tiger Force, charges that Nijjar rejected.

The newspaper quoted three sources as saying that the suspected killers never left Canada after Nijjar’s slaying and have been under police surveillance for months.

It is not known whether the RCMP are expected to arrest any suspected accomplices in the slaying. The police declined to comment on the matter.

The Washington Post reported in September, citing video footage and witness accounts, that at least six men and two vehicles were involved in the killing of Nijjar who worked as a plumber.

Canada’s allegations of Indian involvement in Nijjar’s killing were buttressed when US authorities announced last month they had foiled a plan to kill a Canadian-American Sikh activist in New York and uncovered apparent links to the slaying of Nijjar and threats to three other Canadian Sikhs.

A criminal indictment unsealed in New York said that Nikhil Gupta, an Indian national who was arrested in the Czech Republic in June, allegedly arranged the murder for hire of US-based Sikh activist Gurpatwant Singh Pannun, general counsel for the New York-based Sikhs for Justice.

Gupta allegedly told a US undercover officer less than two weeks before Nijjar’s death that there was a “big target” in Canada. Gupta was allegedly recruited by an Indian government employee to “orchestrate the assassination” of Pannun. The Indian agent described himself as a “senior field officer” who previously served in the country’s Central Reserve Police Force “and had responsibilities in security management” and “intelligence,” the US indictment said.

The Indian agent agreed to pay $100,000 to a purported hitman, who was an undercover police officer, to kill Pannun in a deal brokered by Gupta, US prosecutors allege.

A few days before Nijjar’s murder, Gupta told the US undercover officer – whom he believed was a professional hitman – that “we will be needing one good team in Canada” to carry out another assassination, the indictment said. He also allegedly told the undercover police officer that the plotters in India would be directing slayings in both countries.

Gupta, who has been charged with murder for hire as well as conspiracy to commit murder for hire, allegedly later told the undercover officer that Nijjar was No. 4 or No. 3 among assassination targets in Canada and the United States.

Trudeau told parliament in September that Canadian intelligence had identified “credible allegations” of a link between Nijjar’s death and agents of the Indian state. He made the announcement in the House of Commons after the Prime Minister’s Office learned that The Globe planned to publish the story based on national security sources. The Globe story was published shortly before Trudeau rose in the Commons.

Before airing the accusation in Parliament, Trudeau said he had raised the allegations “in no uncertain terms” with Prime Minister Narendra Modi at the G20 summit in New Delhi in September but he was given the cold shoulder. Canadian Security Intelligence Service chief David Vigneault and the Prime Minister’s national-security adviser Jody Thomas also travelled to India to present the findings. US President Joe Biden also raised the alleged murders-for-hire plot directly with Modi.

Since the US indictment was made public, Modi has said that New Delhi is "ready to look into the alleged plot to kill Pannun but has made no similar commitment to Canada over Nijjar's death.

New Delhi has denied any involvement in Nijjar’s death, insisting that Canada has not shared credible evidence to show Indian agents were behind the killing. Canada said it could not make public more evidence because of fear of jeopardising the ongoing investigation but media reports quoted a Canadian government official as saying the allegation was based on surveillance of Indian diplomats in Canada, including intelligence provided by a major ally, believed to be the US.

Trudeau told The Canadian Press news agency in a year-end interview that the allegation of Indian involvement that he made in parliament was intended to be an extra "level of deterrence" to keep Canadians secure amid safety concerns voiced by Canada’s Sikh community.

“The decision to share these allegations on the floor of the House of Commons was not done lightly,” Trudeau said. “We are not looking to provoke or cause problems but we are unequivocal around the importance of the rule of law and unequivocal about the importance of protecting Canadians.”