I'll be asking my friends in Québec, but I think this group are far-right xenophobes who have done similar disgusting acts.
There is an error in the article, unrelated to the attacks. Limoilou is very much "Québec City proper". It is not the heart of the old city, but is an old thoroughly urban neighbourhood, mostly triplexes similar to Montréal, with a slightly different configuration, and was founded a good century ago. You can easily walk there from le Vieux-Québec. That is where our friend Boom Boom was hospitalised and died, an I'm so sad thinking of that, as he was in quarantine and I couldn't go visit him, as I'd planned - I'd already arranged with my friends who live very close to that hospital to stay at their place.
Many of the small Muslim community in Québec are former Laval University students from francophone North and West Africa. They have always been well integrated in the local society and a great asset to a place that is lovely in many ways, but rather too "pure laine".