Dyfed-Powys Police said the remains have not yet been identified, but has informed the family of a missing Lithuanian man who was staying at the hotel of the development. A Home Office post-mortem has also been arranged.
A man was arrested on suspicion of arson shortly after the incident and the police are now in consultation with the Crown Prosecution Service over the discovery.
The fire originally broke out at the property at 2.21am on 25 July, and attending crews were met with a “well developed fire” and rescued nine adults and three children from the affected property. The hotel was still too dangerous to enter three weeks after the blaze tore through the property.
A statement by Mid & West Wales Fire and Rescue Service at the time said: “At present one person remains unaccounted for. The fire has spread to adjoining properties and the fire service are currently working hard to prevent further fire damage. Residents from adjoining properties have been evacuated to alternative accommodation.”