A walk on the beach turned into a bit more harrowing of an experience than a man who was walking his dog expected last week. While walking along a Vancouver beach in British Columbia, Canada, a man and his dog came upon a shoe with a foot still in it, along with part of a leg.

The foot is the 13th that has washed up on the shores of the Canadian coastline in the last 10 years, according to CNN. Not only did the shoe still have a foot in it, there was also a bit of leg attached to the foot as well, part of the tibia and fibula bones were still identifiable coming from the foot.

The feet that were discovered before this were all human, according to the British Columbia Coroners Service, CNN reported. The Coroners Service and the Royal Canadian Mounted Police told Chek that the foot and leg were likely human remains, based on early analysis, and that further testing would help confirm this and help officials identify the deceased person the remains came from.

Of the previous feet that were found, some were identified as those belonging to people who had died either by accident or due to suicide. Storms on the coast or people lost at sea could also easily have resulted in the floating feet. More than 500 people in Canada die due to unintentional water-related fatalities every year, according to the Canadian Red Cross. It’s unclear why the feet are washing up on British Columbia shorelines specifically, but a spokesperson for the Coroners Services told CNN that there is no reason to believe the feet are all connected.

When another foot was found in 2016, a professor and forensic expert told BuzzFeed that the feet that were found were likely well-preserved due to the type of shoes they were found in. Sneakers and socks help protect the feet from creatures and the other elements of the water, while also causing the feet to float and eventually end up along the shore.

But still, others have their theories. One man who found one of the feet in 2008 told the Guardian that he thought there was someone intentionally doing this to people. Authorities, however, have said if there was any sort of mechanical force involved they would know, as all the feet so far have shown natural breakdown.