Australian newspapers lead their front pages in Australia on Feb. 14, 2013, with the story of Ben Zygier. / William West, AFP/Getty Images

by Oren Dorell, USA TODAY

Two years ago, a man known only as Prisoner X was found dead hanging in his cell. His identity was considered a state secret, and his death was never reported.

After months of silence, Australia's foreign minister on Wednesday confirmed that Prisoner X was Ben Zygier, an Australian-Israeli. What the minister did not say, but what has been reported in news media, is that Zygier worked for Mossad, the super-secret intelligence agency suspected of assassinating Israel's enemies worldwide.

The revelation is sure to create a major predicament for Israel. The disclosure casts unwanted light on the vaunted Jewish spy agency known for complex and effective "hits" and technological sabotage against Israel's foes, and could fray relations between two allies.

The scrutiny also risks impeding the hard-to-come-by intelligence that Israel provides the West on sensitive matters like Iran, a former Mossad operative says.

"Extremely significant" is how former Mossad operator Michael Ross describes the situation and its impact on Western nations that rely on the intelligence only Israel obtains.

Ross, author of the memoir The Volunteer: The Incredible True Story of an Israeli Spy on the Trail of International Terrorists, says Mossad is invaluable to gathering intelligence on a region of great interest and concern to the world.

"The idea of using Israeli citizens with capability of operating under cover in the Near East is going to come to a crashing halt," said Ross, a Canadian who joined the Mossad after traveling to Israel and converting to Judaism.

Little is known publicly about what Zygier was doing for Mossad, why he was jailed in secret and how he killed himself in a cell monitored by video.

Australian and German media reports say the 34-year-old father of two worked in an elite Mossad unit and may have turned on Israel in some way, forcing Mossad to keep him in seclusion for fear of what he might reveal to enemies.

Ross said Zygier worked in a unit that fielded operatives known as "combatants," assassins and spies whose work comes about as close to the fictional British 007 agents as exists in real life.

Zygier's secret incarceration indicates Israeli authorities felt he may have revealed crucial information about Mossad operations, information that enemy intelligence agencies could use to discover the identity of other Israeli operatives, Ross said.

Zygier moved to Israel in 2000 and served in the military, married and became a lawyer before joining the Mossad.

The Australia Security Intelligence Organization (ASIO), Australia's spy agency, suspected that Australian Jews working for the Mossad were using their Australian passports to conduct spy missions in Middle Eastern and Southeast Asian countries, ABC reported. Mossad uses foreign passport holders because Israeli citizens are barred from most Middle Eastern countries where enemies threaten it, such as Syria, Sudan, Lebanon and Iran, Ross.

Former Australian prime minister Kevin Rudd, who was in power when Zygier was arrested in January 2010, is demanding Israel reveal why Zygier was imprisoned.

"That is important, we still do not know," Rudd said Thursday in The Sydney Morning Herald. "Was there any connection between this case and that concerning the illegal use of Australian passports by Israeli intelligence services?"

While it's unclear what Zygier was doing for the Mossad, his incarceration in solitary confinement without trial is a sign that "whatever he was doing using his passport in the Middle East he may have disclosed that to the Australians," Ross said. Australia and Israel are on good terms, but the ASIO is considered "leaky," Ross said.

The possibility that Zygier revealed what he'd done and where he'd been "is enough to make everyone very panicky" in the Mossad, Ross said. "The unit he belonged to is highly compartmentalized, he's at the very, very sharp end of Mossad operations."

Ross says the media reports make it clear that Zygier was working in the same Caesaria unit of the Mossad that he says he worked in for 13 years until 2002. Caesaria operators are considered "combatants" as opposed to agents or case officers who handle informants in foreign countries. Combatants are those authorized to gather intelligence themselves, or to kill enemies of Israel anywhere.

Ross said Zygier's training would have been much like his own. He says Caesaria members undergo extensive psychological screening to weed out people who can't cope with the stress of life under cover, alone and in enemy territory.

Ross says the training involves completing a series of tasks on the street and living alone in a safe house for more than a year, "learning what it's like to live under cover," and how to do it anywhere without raising suspicion, he said.

After completing the training, Ross was provided a "cover story" and a foreign identity and sent to work in Africa, the Middle East and Southeast Asia.

"Caesaria operates a cadre of highly trained deep cover operatives to work anywhere in the globe, any type of covert operation, they're able to do it anywhere at any time," Ross said. "It's the spear point of Mossad operations worldwide."

Zygier changed his name and had employment papers saying he worked for a satellite communications firm in Milan, Italy. Passport stamps showed he visited Iran several times, says the German paper Der Spiegel.

He also had stamps in his passport showing he'd been to Lebanon and Syria, according to other media reports. Travel to those countries indicates he was probably looking for Iran's nuclear sites where the Islamic nation is suspected of engineering nuclear weapons, Ross said.

Mossad never discusses its operation, but it is suspected by most nations of many successful intelligence offensives whose actors have not been found. Such operations go back to the 1960 abduction in Argentina of Adolph Eichmann, the Nazi who carried out the Holocaust in which 6 million Jews died. Other operations include:

-- The intelligence that laid the groundwork for the daring rescue in 1976 of 102 Israeli airline passengers whose flight was hijacked by Palestinian terrorists and taken to Entebbe, Uganda, where President Idi Amin welcomed the hijackers. Twenty-nine Israeli military commandos landed four transport planes unannounced at the Entebbe airport. They killed 45 Ugandan soldiers and six terrorists, loaded the passengers onto the cargo planes and blew up 11 Ugandan fighter jets to prevent them from being used for pursuit.

-- Numerous assassinations of terrorists in Arab and European capitals, such as the 2008 slaying of Hezbollah leader Imad Mughniyah with an exploding headrest in Damascus.

-- In 2010, a hit team of men and a woman traveling on forged British, Irish, German and French passports arrived at a hotel in Dubai and suffocated Hamas military commander Mahmoud al-Mabhouh in his room. Some members of the team could be seen on hotel video surveillance cameras walking about the hotel dressed in tennis gear with racquets so as not to arouse suspicion.

Israel is keen to keep secret any information on the methods and actions of Mossad. Israeli Prime Minister Benjamin Netanyahu suggested the press back off Mossad.

Ely Karmon, a senior research scholar at the International Institute for Counter-Terrorism at the Interdisciplinary Center in Herzlyia, Israel, says Mossad is different because of its reach and independence. Unlike the CIA, which is prohibited by law from many activities overseas such as political assassinations, no Israeli law governs Mossad operations outside the country.

Ross believes any curtailment of Mossad's intelligence gathering would hurt Western intelligence agencies. For American intelligence agencies, who "every day exchange big fat envelopes of information" with the Mossad, Ross said, the Zygier case means "those envelopes are going to be a little bit thinner."

But Reuel Marc Gerecht, a former CIA officer who focused on recruiting Iranian informants in the 1980s and 1990s, doubts it. He says the CIA is generally suspicious of foreign intelligence sources and does not rely much on intelligence from the Mossad.

Yet a few weeks before the terrorist attacks of Sept. 11, 2001, Mossad agents notified U.S. authorities that as many as 200 terrorists had entered the United States in preparation for a major terrorist plot.

And many analysts believe the Mossad is behind a series of assassinations, explosions and computer sabotage operations that have disabled and slowed Iran's nuclear program, which the West has been trying to have ended.

Zygier's travel history indicates he had "very sensitive information about very sensitive operations," Karmon said. "All these areas are places where Israel has enemies, terrorist activity, missiles against Israel and smuggling to Hezbollah (in Lebanon). Probably he knew about these operations."

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