A picture of a pigeons’ nest made entirely from used syringes has been shared by police in the Canadian city of Vancouver to highlight its drug crisis but experts have questioned its authenticity.

Shared on social media by Superintendent Michelle Davey, she said it had been found in a single room occupancy in the Downtown Eastside area of the city, The Independent reported.

She described the image as reflecting the “sad reality of the opioid crisis” in the city.

She also added “#notstaged”—a claim disputed by some social media users who have said it is a hoax.

Luc-Alain Giraldeau, a scientist at l’Universite du Quebec a Montreal, told the National Post newspaper that he was certain the image did not show a real pigeons’ nest.

He said it contained too many eggs as pigeons usually only lay two at a time. He added that it lacks the thick coat of pigeon feces that the birds typically use to keep their eggs warm. Pigeon nests are “always constructed on a flat surface”, he said.

He declared: “This cannot be a pigeon nest.”

Marion Chatelain, a postdoctoral fellow at the University of Warsaw specializing in the urbanization of wildlife, agreed.

“To the best of my knowledge, feral pigeons do not use human wastes to build their nest,” she wrote in an email to the National Post, adding that it is very peculiar to see more than two eggs in a nest.

Nathaniel Wheelwright, a veteran bird biologist at Maine’s Bowdoin College, told the newspaper, “My first reaction was that it looks faked.”

However he added: “But then pigeons do build flimsy platform nests of thick twigs and house wrens sometimes nest in bags of nails. So, it could be.”

Regardless of the authenticity of the image, it has served to draw international attention to the city’s problem with prescription opioid abuse.