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Bill Essayli, an attorney for the United States in California, speaks on Tuesday in Los Angeles as U.S. and Canadian officials announce dozens of alleged members of a transnational organized crime group have been charged and arrested.David Swanson/Reuters

Authorities in Canada, the United States and Europe have arrested and charged dozens of alleged members of India-based transnational crime syndicates, some of whom the U.S. Attorney-General said in court documents played key roles in the 2023 slaying of Canadian Sikh separatist Hardeep Singh Nijjar.

A recently unsealed indictment accuses Indian criminal gang leader Lawrence Bishnoi and his North American lieutenant Satinderjeet Singh, also known as Goldy Brar, of ordering “the assassination” of Mr. Nijjar on June 18, 2023, in Surrey, B.C. Mr. Nijjar is referred to as “H.S.N.” in the document filed in a U.S. court on July 1.

This allegation has been reported by Canadian and U.S. media before, but it’s the first time it has moved to a formal U.S. federal grand-jury charging document.

Officials at a Los Angeles press conference said they are seeking the extradition of Mr. Bishnoi, who operates from jail in India, among others.

More to come.