"It was luck, pure luck, that we managed to track him down, establish contact with him, and bring him to Israel in the end," a former top Mossad official who was involved in Mordechai Vanunu's capture, recalled this week.

The original report that a worker at the Dimona nuclear plant named Mordechai Vanunu intended to disclose information to the British Sunday Times reached Israel's security establishment in August 1986, via the journalist Ami Doron. A few years earlier, Doron had tried to publish a book about the Dimona plant, together with former Haaretz correspondent Eli Teicher, but Israel's censorship had flatly banned the manuscript.

In August, a journalist from the Sunday Times contacted Doron, asking for help about a person named Vanunu who claimed he worked in the Dimona reactor. Doron relayed the information to a friend, Yoav Deigi. Since security at the reactor is not the IDF's responsibility, the information was passed on to the Shin Bet security service and the Mossad and a "steering committee" was created, with key security figures, such as the Shin Bet's Yossi Ginossar and then deputy Mossad head Shabtai Shavit, as members.

What was called the "prime ministers' club" - prime minister Shimon Peres, his designated replacement under rotation agreements Yitzhak Shamir and defense minister Yitzhak Rabin - decided the authenticity of the information on Vanunu should be checked, that Vanunu should be tracked down, and that an effort should be made to prevent him from disclosing information. This assignment was given mostly to the Mossad, since it is responsible for secret missions outside the country's borders.

Shabtai appointed "B," a Mossad veteran with experience directing agents who was then waiting for a new appointment, to head the damage control effort.

The security establishment received information indicating that Vanunu was to be found in Australia. A joint Mossad-Shin Bet team went to Australia, but was unable to find the technician. By studying passenger lists and border crossing information, security officials concluded that Vanunu was in London. A number of consultations were held: officials decided that if Vanunu were found in London, and if there were a need to bring him to Israel against his will, the kidnapping would not be done on British soil.

Between 1981 and 1985, intelligence relations between Israel and Britain were soured by a number of embarrassing incidents. The first occurred when a courier lost a bag that contained forged British passports in a supermarket in Germany. The passports were to be used by Israeli Military Industries officials who sought entry to China. Another incident involved a Mossad agent who infiltrated a PLO cell in Britain. Members of the cell were arrested on suspicion of involvement in the murder of a Kuwaiti caricaturist whose work ridiculed Yasser Arafat. During interrogations, one member of the cell, a Druze from the Golan Heights, admitted he was a Mossad agent. British security officials were angry the Mossad hadn't shared information which might have prevented a murder, and they expelled some Mossad agents who worked in Britain under diplomatic cover - this move effectively shut down Mossad operations in Britain.

When the Vanunu situation arose, the Mossad decided not to conduct a kidnap operation on British soil, and Shimon Peres welcomed this position due to his desire to avoid another embarrassing entanglement with the "iron lady," prime minister Margaret Thatcher.

A Mossad team, including Cheryl Bentov, nicknamed "Cindy," after her brother's girlfriend (and today his wife), combed through London. With the help of information culled from various sources, the Mossad managed to track down Vanunu. It identified his hotel and kept tabs on his contacts with the Sunday Times.

In Tel Aviv, Shimon Peres was at this point alarmed by the prospect of public disclosure about his "baby" - the Dimona reactor. He convened a meeting of the newspaper editors committee and in an off-the-record talk implored them not to print reports based on stories in the international press about the Dimona plant.

Information about the importance accorded by Israel's prime minister to the subject was leaked via an Israeli journalist to the Sunday Times, and the British newspaper decided after a two-week period of vacillation that the story told to them by Mordechai Vanunu was genuine and important.

The special security team established to work on the case formulated a few possible action scenarios. One proposal, which was not taken very seriously, was to kill Vanunu, rather than trying to kidnap him and possibly bungling the operation. It was clear to security officials that this proposal was, at most, wishful thinking - since the establishment of the state, Israel's security services had never assassinated an Israeli citizen.

Mossad agents continued to comb the streets of London with a picture of Vanunu in their pockets. In an incredible stroke of luck, "Cindy" found Vanunu as he was staring at a store window in Leicester Square. She stood alongside him, and established eye contact with him. Vanunu, who (according to family members) was normally shy with women, summoned the courage to talk with her.

"Are you also a tourist," he asked "Cindy." She identified herself as a cosmetician by profession, and a Jewish American who was touring London. Vanunu invited her for coffee; she played hard to get. Vanunu was hooked.

On September 30, the Sunday Mirror released Vanunu's picture and a report ridiculing the Dimona nuclear reactor disclosure, in an attempt to belittle the Sunday Times, which was about to purchase Vanunu's account. Vanunu was upset, and Cindy exploited his high-strung state. She proposed they leave the following day for Rome, where her sister had an apartment. Though the Sunday Times journalist Peter Hounam explicitly warned Vanunu that Cindy might by a Mossad agent, and that he must not leave British soil, Vanunu took up her offer.

After they flew to Rome, and entered the apartment, two Mossad agents pounced on Vanunu, tied his hands, and injected him with a drug. He was then brought back to Israel by boat.

Cherly Bentov told Haaretz in a telephone interview that she didn't want to discuss the Vanunu story. Bentov, 44, lives in Orlando, Florida with her husband, Ofer, who is a former IDF intelligence officer.