Officials at the mosque in Chicoutimi have not filed a complaint, the Canadian Broadcasting Co. reported.
The CBC quoted Moustafa Elayouby, who is in charge of the mosque, as saying he does not believe the act is characteristic of Quebec.
No one has claimed responsibility for the vandalism, the CBC said. A letter was left at the mosque, called Mosquée de Saguenay, denouncing Islam.
The CBC said the vandalism comes as the Quebec government is introducing a "secular charter," which would ban hijabs and other religious clothing and symbols.
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