A police team formed to investigate afresh Congress leader Shashi Tharoor’s wife Sunanda Pushkar’s murder has started work, Delhi Police Commissioner B.S. Bassi said .

“The special team is looking into each and every possibility of the case. Whatever is needed will be done,” Bassi told the media.

Asked if Tharoor, a former central minister and now a Congress MP, would be questioned, he said: “We will do, if needed.”

On Tuesday, the police said a case of murder had been registered against “unknown persons” after a medical report confirmed that Pushkar, found dead in a luxury hotel here in January 2014, was poisoned to death.

Informed sources said that a Delhi Police team visited the Kerala Institute of Medical Sciences in Thiruvananthapuram last month to speak to doctors who had treated Pushkar.

Pushkar, 52, was found dead in mysterious circumstances a day after she and her husband checked into the hotel because their house was getting painted.

After police announced Tuesday that Pushkar was murdered, the Bharatiya Janata Party and the Communist Party of India-Marxist in Kerala asked Tharoor to quit his Lok Sabha seat.