:Look, this page, which is definitely pro-Islamic and so has no reason to downplay the religion's presence in Mexico, says that Torreón has "a small Muslim community", with only 10–20 people who show up for jumu'ah. That hardly seems to place it among "North American cities with high concentrations of Muslims". The presence of significant numbers of Muslims in the other cities listed isn't hard to confirm (and the last time I looked Toronto isn't a "US city"), but Mexico doesn't even gather census data on non-Christian religions. It doesn't seem unreasonable to ask for some sourcing for the IP's addition.