"The request came suddenly and though I had never done anything like that in my life, I said I would do it," says Professor P V Viswanath, who would spend more than five hours on November 27 from midnight in conference calls with a terrorist who said his name was Imran. The drama, which could not save the lives of six Israelis in Chabad House (formerly Nariman House) in Mumbai, involved a fellow rabbi leading the negotiation and at a later stage, the Federal Bureau of Investigation.

"The situation became even more urgent and personal as I knew Rabbi Gavriel Noach Holtzberg, who ran the Chabad House in Mumbai, welcoming Jewish travellers from across the world," the professor recalls. "Just last summer, he and his wife had invited my son and me to Chabad House while we were visiting the city."

Viswanath, who grew up in Mumbai and spent more than 20 years there, describes himself as an orthodox Jew (without going into any personal details), spoke to Imran, with Rabbi Levi Shemtov, director of the Washington office of American Friends of Lubavitch, leading the discussion. The primary concern was to know what the terrorists wanted for the release of the Jews at Chabad House.

"The gunman who called himself Imran was so calm throughout the several conversations I had with him that anyone hearing us talk would have thought they were just normal calls," says Viswanath. Rabbi Shemtov had set up conference calls between Washington, DC and New York and Holtzberg's cell phone in Mumbai, which was being answered by Imran.

Rabbi Shemtov knew the hostage situation at Chabad House when he called Rabbi Holtzberg on his cell and the man who took the call kept on saying, 'Urdu, Urdu, Urdu'. Rabbi Shemtov then knew there was an urgent need for a translator from the Jewish community.

"He contacted me through my nephew," said Viswanath. "He found out about me through the Jewish grapevine."

Viswanath did not know what to call the hostage taker, but the man asked Viswanath to call him Imran. "I would then initiate the call by saying Salaam Aleykum. And he would respond saying Wa Aleykum As-Salaam. I did not call him by his name. I would simply say in Urdu, Aap."

At the beginning of the negotiations, Imran calmly said, "Put us in touch with the Indian government and we will let the hostages go." He finally hung up when the Jewish group in New York contacted a police official, whose name they do not know, and lost contact with Imran.

When the commandos ended the siege, they found six Israelis including Rabbi Holtzberg and his pregnant wife dead.

Imran spoke very good Urdu, says Viswanath, who describes his own Urdu as adequate. He added that there was no communication problem or any misunderstanding, though at first Viswanath was worried if there would be any communication glitches because of the Urdu dialects. "His certainly was not Hyderabadi Urdu, it was mainstream Urdu though it had no big, difficult to understand words," said Viswanath.

A graduate of Sydenham College, Mumbai, Viswanath can still fluently converse in several Indian languages including Urdu and Hindi despite living in America for 30 years.

"The tension was huge, but we all kept the calm," Viswanath, who is known in Jewish circles as Mylekh, said.

Viswanath is a professor of finance at the Lubin School of Business at Pace University, New York. He first spoke about his experience to the Jewish publication Forward.

"We did not ask the gunman why he was holding the Jewish people hostage," he continued. "Imran never made any statements against Israel or anything that could be deemed anti-Semitic."

"He would not let us talk to Rabbi Holtzberg or anyone else in Chabad House but he took our calls for over five hours." He could have been speaking from a corner in the house, Viswanath, who was familiar with the layout of Chabad House, says. "We heard no noise or commotion in the background."

Viswanath recalls that Imran's calmness did nothing to slow down his own racing pulse. Imran spoke in a soft voice but would not divulge much; when he was asked at the beginning of the conversation where he was, he said something like, "You know where I am speaking from."

The rabbis in DC and New York asked him several times about the condition of the hostages and each time he said everybody was fine. 'At one point, we asked him if all the people there were conscious, because we had heard reports that some of them were unconscious,' Viswanath wrote in his first person piece in Forward. 'Imran told us that everybody was fine: Nobody was hurt and they had not touched anybody. We haven't even slapped them around, he said.'

One of the few times Imran lost his cool was when he was asked how many people he had in his team at Chabad House. He said it was an irrelevant question, mocking the negotiators and asking them if they were serious about 'saving your friends'.

'Keep to business matters and think of how to do what we are asking you to do,' he said. Imran had also heard late during their conversation that one of his team mates had been captured.

"It was not clear to us at that time where the man was captured," Viswanath says. "Now, Imran was demanding that the man should be brought to Chabad House" and that meant the negotiators had to facilitate that by speaking to the Indian government."

"Calmly, Imran told us, 'Do this and we will let your friends go'."

When the police officer lost contact with the rabbis in New York, it was about 5.30 am on November 27. Viswanath says, given the chaotic conditions in Mumbai, the rabbis in America were not able to discuss anything substantial with the officer.

Viswanath also remembers telling Imran that the organisation was trying to find other high-ranking officers, but Imran switched off the phone. "We tried calling him many many times over many hours, but he would not take the call," Viswanath says.

Viswanath now knows that even as he was speaking with Imran, the police had cut off the power supply to Chabad House and the building had been surrounded by Nastional Security Guard commandos.

"But there was no fear or uncertainty in his voice," he says. "It was as if he were doing some business negotiations."

Viswanath has also said that FBI had passed on tips for dealing with hostage takers, but the negotiating team had no opportunity to use them as by then Imran terminated contact.

The professor also said that he waited, along with the rabbis, for many hours hoping to renew the contact. By then he was hearing from his friends in Mumbai that Holtzberg's nanny Sandra Samuel had escaped with the rabbi's baby son Moshe whose clothes were soaked with blood. She had told the friends and fellow Jewish leaders that the Holtzbergs had been unconscious when she left.

His hopes then began sinking, Viswanath says. With hindsight, he wonders if Imran was serious about negotiating with the government.

Many days have passed since the attacks, but Viswanath cannot put those tense hours behind him.

"I still continue to mourn for the dead in Chabad House," he says. "Surely, I also feel for people of other faiths, Hindus and Muslims who died in these attacks in my city. But I also see a divine thing in this horrific tragedy. I see the people of Mumbai being united to stand up to this kind of attacks."