"There is no evidence to suggest a break-in at the mortuary, and no evidence to suggest that any staff from the mortuary, or indeed any other council employees, are involved in any wrongdoing," police in nearby Wiltshire said late on Monday.
Sala's plane came down in the English Channel as he flew to Cardiff on January 21, two days after completing his transfer from French side Nantes to the Welsh club.
The 28-year-old's body was recovered but that of the only other person on board the small Piper PA-46 Malibu, 59-year-old British pilot David Ibbotson, has never been found.
Police Detective Inspector Gemma Vinton said: "My thoughts remain with Emiliano's family for the pain they have endured throughout the last three months, and who should not have to go through the additional anguish of knowing such distressing images have circulated on the internet.
"I would also urge people to stop sharing the image – this is causing further distress to Emiliano's family and friends."