NEW DELHI: Former Indian minister and former United Nations diplomat Shashi Tharoor may be questioned by Delhi police after they opened a murder investigation against “unknown persons” following the death of his glamorous wife.

Sunanda Pushkar was found dead in her five-star hotel room in the Indian capital in January 2014, after publicly accusing Tharoor of having an extra-marital affair with a Pakistani journalist.

Almost a year after her death, police opened a murder investigation on Tuesday. Tharoor has not been identified as a suspect.

“Whatever is necessary will be done,” Delhi Police Commissioner B S Bassi told reporters on Wednesday when asked if the police would interview Tharoor, who has cooperated with investigations since the death.

Also read: Shashi Tharoor's wife found dead in hotel

After an autopsy initially concluded Pushkar probably died of an overdose of anti-depressant drugs, Indian police said on Tuesday that she was poisoned and a case was registered.

Tharoor said he was “stunned” to hear his wife's death was being investigated as murder, adding that he had never suspected foul play.

“We all want that a comprehensive investigation be conducted and that the unvarnished truth should come out,” he said in a statement.

The couple were married in late 2010, the third marriage for each. As part of Delhi's social set, they frequently figured in the society pages of newspapers.

Know more: Shashi Tharoor's wife died 'unnatural death': autopsy

Tharoor was a junior education minister at the time of Pushkar's death. He remains a member of parliament for the Congress party, which has ruled India for most of the time since the nation gained independence.

In a letter to Bassi in November, Tharoor accused Delhi police officers of attempting to frame him and using physical coercion to try to intimidate his domestic help into “confessing” they had murdered Pushkar together, media reported.

An acclaimed author and prolific user of social media website Twitter, Tharoor was an under-secretary general during Kofi Annan's leadership of the United Nations.

In 2009, Tharoor won a seat in India's parliament from the southern state of Kerala and was later appointed the junior foreign minister.

He resigned in 2010 over allegations of corruption in winning a cricket league franchise after Pushkar was allegedly given stakes worth about $15 million for free.

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