Blunt force trauma has been determined to be the cause of death of 31-year-old Sarah Smith and her two young children, a son Genuine and daughter, Phoenix.
This follows a postmortem which was performed at the Scarborough mortuary on Monday.
The bodies were discovered in a decommissioned tank owned by the Water and Sewerage Authority (WASA) in Parlatuvier, Tobago on September 10.
Smith, who owned a small shop not far from where she and her children were found, was reported missing by her mother on September 2.
In spite of the findings of the autopsy, police have not classed their deaths as a murder as a determination now needs to be made on how the injuries were sustained, as police noted that it was possible that the trauma could have been caused as a result of a fall.
The injuries were said to have been about the body, with the fatal trauma being to the heads of the three deceased.
A toxicology report is expected to be done.