Wiltshire Police confirmed an investigation had been launched following the discovery. Officers were spotted in an area close to Junction 15 of the M4 near Swindon on Friday, July 2.
The force found what appeared to be “old human remains” in a patch of woodland and are currently searching the area off Medbourne Lane.
A force spokesman said: “Specialist officers are currently conducting a meticulous search of the area to recover any relevant material before forensic scientific analysis is conducted.
“This sort of investigation can take a number of weeks however we will endeavour to provide updates where we can as this work continues.
“Members of the public will see a police presence in the area over the next few days and weeks.”