Toronto: Sikhs turned up in large numbers at a Khalistan referendum event in Canada just as Prime Minister Narendra Modi conveyed New Delhi's strong concerns about continuing anti-India activities in the North American nation to his counterpart Justin Trudeau at the G20 Leaders' Summit.

The vote to weigh support for Khalistan was held on Sunday in the British Columbian province of Surrey at the Guru Nanak gurdwara, where its former president Hardeep Singh Nijjar was shot dead in June.

The outlawed Pro-Khalistani group Sikhs for Justice (SFJ), which organised the referendum, said more than 100,000 people attended the event, the Global News channel reported.

“The turnout tells us, and the wider community, that the issue of Khalistan is not an issue for a fringe group of people, rather this is a deep-rooted issue that touches the hearts and minds of many Sikhs,” Jatinder Grewal, an SFJ director, told the Vancouver-based news channel.

The vote was supposed to be held at a school in Surrey, but was cancelled after images of weapons on the poster were brought to the school authorities' notice by concerned residents.

In a strongly-worded condemnation, Modi told Trudeau on Saturday that the extremist elements are promoting secessionism and inciting violence against Indian diplomats, damaging diplomatic premises, and threatening the community in Canada and their places of worship.