Sunanda Pushkar Tharoor was found dead in her hotel room on January 18.
Sunanda Pushkar, the wife of Congress leader Shashi Tharoor, died of poisoning, and not from an overdose of Alprax anti-depressant pills, according to a report by doctors who have conducted a second post-mortem in the case.
The Delhi Police says that the report, submitted by a team of three doctors from Delhi's premier hospital AIIMS, does not throw any new light on the case because it does not shortlist the substance that killed the 52-year-old; instead, it lists a series of poisonous substances which were traced in samples of Ms Pushkar's viscera or internal organs.
Ms Pushkar was found dead at a five-star hotel in Delhi in January, a day after an angry Twitter exchange with a Pakistani journalist who she accused of having an affair with Mr Tharoor, then a minister in Dr Manmohan Singh's coalition government. He is now the Lok Sabha MP from Thiruvananathapuram.
Doctors had described his wife's death as "sudden" and "unnatural".
Before she was found dead in her suite, Ms Pushkar appeared on NDTV in a television interview with Mr Tharoor. The couple said their marriage remained a happy one.
The first post-mortem report for Ms Pushkar suggested that she had died from likely drug poisoning. The Delhi Police had found used strips of Alprax from her bedroom. The report also said there were 15 injuries on Ms Pushkar's body, but these were described as small and ruled out as a cause of her death.
The case has so far been examined by a Delhi magistrate - under law, a magisterial inquiry is automatic if a woman dies within seven years of marriage. No police case has been filed so far.
Mr Tharoor has repeatedly called for a swift inquiry into the death of his wife. Today, Ms Pushkar's family also demanded a CBI probe.