Social media has been left dumbfounded by a piece of snow art depicting a bear with a very prominent belly button.
An image of the outline of a bear drawn into the snow on the Lachine canal in Canada was posted on Twitter by journalist Kate McKenna on Thursday prompting the question of how the anonymous artist gave it a belly button without marking the snow around it.
Multiple theories are circulating the internet, with one of the most mentioned being that it was achieved by the artist jumping into the middle of the drawing to make the belly button mark.
But Ms McKenna shut that theory down by describing the bear as very big, requiring a large, precise leap onto the icy and potentially dangerous waterway.
Fellow writer Tracey Lindeman said the artist could have reached the middle of the bear with a hockey stick - a proposition Ms McKenna found very "interesting".
The mystery deepened when the Lachine Canal Twitter account, which describes the canal as "more than an inland waterway" but also an "urban park that astonishes", replied to the tweet.
"For safety reasons it is forbidden to venture on the Lachine Canal during winter," it said.
Some have theorised snowballs may have been used, but one user suggested this would have required "very good snowball aim".
Ms McKenna later said she was leaning towards the view that the belly button mark was there before the bear was drawn, potentially from a bird landing.
User Salgood Sam analysed the drawing and uploaded a high resolution version illustrating how the mark could be from a bird if the snow was light and fluffy enough for the bird's wings to make an impression.
Others speculated the belly button could have been achieved by an "alien-controlled drone "or that the bear came to life and added it himself.
Alas, the mystery remains unsolved, but Ms McKenna said a new season of True Detective could be based around this unfolding conundrum.