Mary Bowerman

USA TODAY Network

A severed foot, still inside of a running shoe, is the 13th dismembered foot to wash up on the shore of British Columbia since 2007, according to the British Columbia Coroners service.

The shoe was sold in North America in March 2013, leading authorities to believe the person died between 2013 and December of last year.

“Preliminary examination suggests that the foot disarticulated naturally from the rest of the body, a result of prolonged immersion in water,” The coroner's office said in a statement.

The foot was found on Feb. 7 by a family walking along Botanical Beach on Vancouver Island, according to Canadian Broadcasting Corporation news.

Charlotte Stephens told CBC that her husband picked up the shoe and didn’t notice anything unusual at first.

"He … brought it out on to the beach, and 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," Stephens told CBC.

The coroner's office is working with local authorities to identify the person and try to determine the cause of death.

The dismembered feet have sparked numerous theories about what could be causing the grisly discoveries. In 2008, a year after several feet washed ashore, The Toronto Star reported that, "speculation ranges from natural disasters, such as the tsunami of 2004, to the work of drug dealers, serial killers and human traffickers."

To date, authorities have been able to identify 10 of the13 feet that have washed ashore in the last nine years.

“In none of the cases was any foul play involved,” the coroner’s office said.

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