Investigators said the identity of the remains had not been confirmed Wednesday, The Daily Telegraph reported. Lewis, who had been playing with friends, disappeared Sunday.
"Formal identification procedures will take place but officers investigating are linking this to the 13-year-old boy recently reported missing in Doncaster," a South Yorkshire police spokesman said. "An investigation has commenced into the circumstances surrounding this tragic event."
Scene of the crime officers searched a large field in Doncaster Wednesday.