DES MOINES, Iowa (AP) — Police are investigating the discovery of human remains in a homeless camp near downtown Des Moines as a homicide. Television station KCCI reports that the police received a tip Tuesday that led investigators to a wooded area behind an abandoned manufacturing plant.

Police Sgt. Paul Parizek says the case is being treated as a homicide, noting that the body had been “cleverly concealed” and that the person did not appear to die of natural causes. He did not share other details of how the person died.

Police says the body was likely in the area for a few months. Officials have not determined the person’s race, gender or age.