Participants at the meeting Saturday said academics, activists, and imams expressed a range of views about the possible motivations of the suspects, who are accused of plotting to bomb buildings and storm Parliament, take hostages and behead the prime minister unless Canada withdrew its troops from Afghanistan.
"It's about time Muslims owned up to the fact it's a Muslim problem," said participant Farzana Hassan-Shahid of the Canadian Muslim Congress, adding she believes the community must forcefully denounce extremism. "We need to be more proactive, rather than issue statements of condemnation."
Harper took detailed notes and assured the group he recognized the concerns of the Muslim community, participants said. The meeting was off-limits to the media, and a call to the prime minister's office Sunday was not immediately returned.
The suspects include 12 men and five youths. Fourteen are due in court on Monday for bail hearings.
Some in Canada have expressed fear of an anti-Muslim backlash. After the arrests were announced June 3, the windows of a Toronto mosque were smashed. On Friday a prominent Muslim imam was attacked outside his Montreal mosque by a knife-wielding man in what police said was a hate crime.
Muslims attending the meeting Saturday included professors from the University of Western Ontario and University of Toronto, as well as a representative of the Canadian Council on American-Islamic Relations.
Tarek Fatah, spokesman for the Canadian Muslim Congress, said issues that came up for discussion included allegations that American-based Islamic organizations are spreading fundamentalism and extremism in Toronto.
"This is America pushing its fundamentalist Islamist thinking into Canada, not vice versa," he said.