Here are the latest developments in this story:
The injection mark has been classified as injury number 10 in a medical report. Doctors conducting the autopsy had found 15 injury marks on Sunanda Pushkar's body, including a bite mark on one of her hands and minor bruises on her arms.
On Monday, the Delhi Police said it had registered a case of murder based on a "final clarification report" from Delhi's All India Institute of Medical Sciences (AIIMS), which said that her death was "unnatural" and that she was poisoned.
The police said they had to register a case to be able to send Ms Pushkar's viscera samples abroad to investigate what poison caused her death; Indian labs have been unable to determine that. The police are expected to seek a letters rogatory for this.
The Delhi police is now expected to draw up a list of people linked to the case to be questioned. Ms Pushkar's husband, Congress MP Shashi Tharoor is likely to be among them, the police have indicated.
Amid many questions on why they took a year after Sunanda Pushkar's death to register a murder case and what was different in the latest AIIMS report for them to have done so, sources in the Delhi Police told NDTV yesterday that new facts in the report had necessitated registering a murder case.
Police sources said the report also has new facts on the injuries found on Ms Pushkar's body.
Police sources also said that the report, received on December 29, said the death seemed "homicidal," the first time, they said, that such a mention was made in a report from AIIMS, where Ms Pushkar's autopsy was conducted.
But Dr Sudhir Gupta, chief of the forensic department of AIIMS, has told NDTV that the report does not mention "homicide." He said the report only says that Ms Pushkar died of poisoning. "It is the prerogative of the police whether to register a murder case or not," said Dr Gupta who led the team that conducted Ms Pushkar's autopsy.
Sunanda Pushkar was found dead in a suite of a five star hotel in Delhi in January 17, 2014. The autopsy report said she died due to poisoning but there was no clarity on whether it was homicide or suicide. A subsequent report from the CFSL (Central Forensic Sciences Laboratory) had ruled out any traces of poison in her body, but the AIIMS team stuck to its stand and had sent a report to the police in September, naming a few poisons that could not be detected easily by forensic labs in the country.
Shashi Tharoor said on Tuesday that he is "stunned" at a murder case being registered in his wife's death. "Although we never thought of any foul play in the death of my wife, we all want that a comprehensive investigation be conducted and that the unvarnished truth should come out," he said, assuring the police of his "full cooperation."
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