However, the nature of the poison and the quantity can only be established after viscera tests at CFSL.
Sunanda, 52, was found dead in a 5-star hotel in South Delhi on Friday night, a day after her twitter spat with Pakistani journalist Mehr Tarar over an alleged affair with Tharoor.
In a report to the police, SDM, who has recorded the statements of Sunanda's brother, son, Tharoor and his staff, had said that no family member suspected any foul play in the death.
The autopsy report had mentioned more than a dozen injury marks on Sunanda's both hands and an abrasion on her cheek which suggests a “use of blunt force”, besides a “deep teeth bite” on the edge of her left palm.
The search and seizure memorandum of the police which is a part of the report mentioned finding of mix of two drugs - Alprazolam and Excedrin.
Excedrin is a combination of acetaminophen, aspirin, and caffeine while Alprazolam is an anxiolytic.
The case, which was initially handled by South District police as the incident took place in Sarojini Nagar area was handed over to the Crime Branch on Thursday.
However, the case was transferred back to the South District police on Saturday.
