After a short respite, athletic shoes containing human feet are once again washing up on Canadian shores, the Guardian reports. Earlier this month, a family visiting a Vancouver Island beach made a "grisly discovery," according to the CBC. "We had a look at it for about five minutes and we thought, 'It almost looks like there is an actual foot bone in it,'" says Charlotte Stephens, whose husband spotted the shoe and brought it onto the beach. It was the first foot sighting in British Columbia in four years. Five days later, another foot in a shoe was found—a match for the first, making the latest two finds a pair. They were the 11th and 12th feet to wash ashore in British Columbia since 2007. Four more have also washed up in Washington state to the south, with the most recent being found in 2014 in Seattle.
Since the feet started appearing in 2007, people have suspected everything from drug dealers to serial killers, the Washington Post reports. The truth is likely much more mundane. Barb McLintock at a coroner's office in British Columbia tells the Guardian the feet almost assuredly come from people who either killed themselves ("People jump off bridges," a criminologist told the Daily Beast in 2011) or were killed by storms. A study once found that when a body is being pushed and pulled around in water, hands and feet are usually first to fall off. Coroners can tell whether bones separated naturally during decomposition or by force, and so far the feet show no signs of foul play. Tide patterns and new shoe designs with air pockets and lighter foam that allow them to float account for why the feet suddenly started appearing in 2007 in the Pacific Northwest. But one mystery still remains: Most of the shoes contain right feet.