foul play

赤字の意味を教えてください。（UG）→てらかど
(CNN) -- Authorities have found what appears to be a severed human foot this week, the 11th found in waterways in British Columbia in the past four years.
The discovery of another foot, this one still stuck in a running shoe, adds to the mystery that has confounded Canadians for years.
A boy found the foot and leg bone Tuesday near a marina in an inlet called False Creek, Vancouver Police said.
Foul play is not suspected, authorities told Canadian Broadcasting Corp. Authorities believe that because the remains did not have any evidence of trauma, the CBC reported.