The body was discovered in Middle Cross Lane, between Harwell Sluice Lane and Everton Lane, after a member of the public notified police on Saturday 2nd February.
A 13-year-old girl is among five people arrested in connection with the incident.
She remains in custody along with a 47-year-old woman and three men, aged 31, 27 and 21.
A cordon remains in place around where the body was found as forensic examinations continue.
Enquiries are underway to identify the victim and trace a next of kin.
Notts Police said a post-mortem examination has been carried out and at this stage the cause of death is inconclusive.
Detective chief inspector Phil Cox, who is leading the investigation, said: “Although we have made five arrests detectives are continuing to make enquiries in the area.”
“We are keen to speak to anyone who might have seen something unusual in the area, particularly between Friday 1st February and the afternoon of Saturday 2nd February.
“If you have any information you believe to be of relevance please contact the incident room on 101 ext 817 1520 or Crimestoppers on 0800 555 111.”