Mumbai, Sept. 4: Peter Mukerjea was today quizzed for the third consecutive day in connection with the murder of Sheena Bora, a day after police claimed they had been able to "crack" his wife Indrani Mukerjea.

Besides Peter, the former CEO of STAR India, his step-daughter Vidhie and Sheena's biological father Siddartha Das also arrived at the police station where both are likely to be questioned in connection with the case.

Peter reached the police station at around 11.20am to record his statement. Vidhie arrived about half-an-hour later, police said.

Siddartha, who claims to be Sheena's father, also reached the police station around 12.30pm, the police added.

Siddartha, a resident of Calcutta, was yesterday quizzed by police on various aspects and his statement was recorded. He was at the Khar police station from 8pm yesterday till 3am in connection with the investigation into the sensational murder committed three years ago.

The police had yesterday claimed that Sheena's mother Indrani had "admitted" to her role in the crime. They are also probing financial details obtained from Peter, who had on Thursday brought along his CA and had bank statements, documents pertaining to the registration of companies and the books of his various companies.

It is not unusual for suspects to say what the investigators would like to hear just to get the interrogators off their back.

The way questioning is carried out in cases with multiple interviewees also plays on the nerves of the suspects. The suspects, persons of interest and potential witnesses are mostly questioned in separate rooms, keeping them in the dark about what the others may have revealed.

They are given separate sets of questions and asked, in some cases, to write the answers down. The different sets of answers are matched and, in case of discrepancies, they are questioned again. Occasionally, they are brought together to drive home the unnerving message that their replies are being matched then and there.

In such a scenario, "the Prisoner's Dilemma", an example used to illustrate the equilibrium associated with the late Nobel laureate John Nash, could come into play. (See chart above)

Yesterday, Peter was in Khar police station and left after 11.30pm, clocking over 12 hours. Yesterday, too, he had been there for over 12 hours.

"Indrani and Peter have been given two sets of questions with the common questions numbering around 25. They have to write the answers down. They will be interrogated on the answers repeatedly to check for information gaps and discrepancies, if any," said a police source.

"Indrani was very stiff during her interrogation - she asked her interrogator whether Peter would support her legally in this case. When another interrogator relayed the question to Peter, he was silent," said a police source.

The police had earlier said that Indrani had been holding out in spite of several rounds of questioning.

The sources said Indrani had been deeply worried about the future of her surviving daughter, Vidhie. Nor has Indrani got any categorical assurance from Peter that he would stand by her, they said.

Whether these two factors had any bearing on her alleged admission is not known.

"How is Vidhie holding up? Is she okay? Is all this affecting her studies? Has she left for Bristol?" an officer quoted Indrani as asking not just her lawyers but also the policemen interrogating her.

Vidhie, who is training to be a pianist, studies at a music school in Bristol. "She was supposed to leave for the UK to get back to her life on Thursday. But the plan changed after Peter, Vidhie's adoptive father, was taken in for questioning. She will now leave for Bristol on Saturday," said a source close to the family.

Siddartha was flown to Mumbai from Calcutta last evening and is understood to have been brought face-to-face with the accused. His statement has been recorded and his sample taken for a DNA test. A senior police official told PTI that Mumbai police commissioner Rakesh Maria is likely to brief the media soon on the progress of the investigation so far.

Peter was questioned till late last night by Khar police. Indrani's ex-husband Sanjeev Khanna and her driver Shyamvar Rai were quizzed in other rooms at the police station. The custody of the three accused - Indrani, Sanjeev Khanna and driver Shyamvar Rai - end tomorrow.