Quebec City police have opened an investigation into the distribution of a pamphlet that makes unfounded allegations about a local mosque.

The pamphlets have turned up in mailboxes in the Sainte-Foy neighbourhood and target the same mosque that was the site of an Islamophobic incident last month.

A pig's head was left outside the Centre culturel islamique de Québec in June. The package was accompanied by a note that read "Bon appétit." Islam prohibits the consumption of pork.

In a recent days, residents have complained about receiving a pamphlet that makes a positive reference to the June incident. It also claims the mosque is linked to jihadist groups and promotes Sharia law and homophobia.

"It's incredible that we can insinuate these things under the cover of anonymity," said Nicole Villeneuve, one of the residents who received the pamphlet.

"It leaves unpleasant traces on the population. We have to denounce this kind of garbage."

The pamphlets are unsigned, but residents described seeing them delivered by a man and a woman.

The head of the mosque, Mohamed Yangui, said the pamphlet wouldn't shake their outlook.

"We are Quebec Muslims," he said. "We will continue to contribute positively to Quebec society."