The body was discovered Saturday near Everton, a village of about 2,000 people in Nottinghamshire, the Daily Mirror reported.
Police said the five people detained are all residents of South Yorkshire. They were described as three men ages 21, 27 and 31, a 47-year-old woman and the teenager.
"All five people have been arrested on suspicion of murder and all are from the South Yorkshire area," a spokesman said. "Officers from South Yorkshire Police have also been assisting the investigation."
While the case is being treated as murder, investigators said the cause of death has not yet been determined. The area where the body was discovered was still being combed for evidence Tuesday.