"When the United Progressive Alliance was there, they were not allowed to question Tharoor. There was a lot of pressure and there were a few police officers who complied with the ruling party. But, ever since November, the police have moved into action. This is a high profile case with so many interests involved. The Indian Premier League matter is also tagged with this. So, I think the police have to move slowly and carefully. Most importantly, find out why Tharoor lied earlier and what is the truth," said Swamy.
"This was already known that she has been murdered. Now we know that the last person to see her was Tharoor. And that she had told press people that she was going to expose IPL. The truth is practically known, the question is who is the killer and who did Shashi Tharoor assist in killing. And then I think Shashi Tharoor needs to be taken into custody," he added.
Earlier in the day, Delhi Police Commissioner B S Bassi had said that things will be analysed and further necessary action will be taken after Tharoor's statement is analysed.
Tharoor was interrogated at the Vasant Vihar police station in South Delhi on Monday evening. According to media reports, he was asked over 50 questions by a team of four officers in the first of three likely rounds of interrogation.
Earlier this month, the police had said that based on available evidence, Sunanda Pushkar, 51, was poisoned.
A case of murder was registered on January 6.
Sunanda Pushkar was found dead in the five-star Leela Hotel in Delhi on January 17, 2014.
Sunanda Pushkar was married to Tharoor for a little less than four years. It was the third marriage for both. Before her death, Pushkar had publicly accused Tharoor of having an affair with a Pakistani journalist Meher Tarar.
Initially, her death was debated as a possible suicide for months, and it was only this month, that a murder theory began to be considered seriously after doctors at the All India Institute of Medical Sciences maintained that her demise was unnatural.
Tharoor has been demanding that the investigation must be "free of political pressure or a pre-determined outcome."
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