The new report by the three-member panel of doctors, who had conducted the autopsy on her, was prepared on the basis of the findings of the Central Forensic Science Laboratory which had examined Sunanda's viscera, sources said.
They said that the team had again concluded like it did in its first report that her kidney, liver and heart were functioning normally and that her death was caused by poisoning.
The new report was submitted to police 9 days ago.
The viscera report of CFSL in March had hinted at drug poisoning but police considered it as inconclusive. It then asked AIIMS to re-examine the report and give its findings.
The 3-member team has now submitted the "Subsequent Medical Board Opinion" to the police on September 30.
Sunanda was found dead in a 5-star hotel in South Delhi on the night of January 17, a day after her Twitter spat with Pakistani journalist Mehr Tarar over an alleged affair with Tharoor.
The probe into the case was handed over to the Crime Branch on January 23. However, the case was transferred back to the South District police two days later on January 25.
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