Ronen Zvulun / Reuters

Israel's Prime Minister Benjamin Netanyahu's government has restricted reporting in Israel on the case, which is overshadowing his victory in a national election held last month.

JERUSALEM - Israeli lawmakers announced plans on Sunday to investigate the 2010 jailhouse death of a reported Australian immigrant recruit to the Mossad spy agency.

The statement by Parliament's Foreign Affairs and Defence Committee followed calls by Prime Minister Benjamin Netanyahu at a cabinet meeting to dim a growing media spotlight on the affair he saw as at risk of jeopardizing national security.

The case kept under wraps for two years then publicized by Australian television last Tuesday involves a 34-year-old immigrant, Ben Zygier, said to be a Mossad operative held on suspicion of security offences, who died of what has been labeled an apparent suicide behind bars.

In a terse communique, the legislative panel's subcommittee on intelligence said it has "decided to conduct an intensive examination of all aspects of the incident involving the prisoner found dead in his (prison) cell in December 2010."

While unlikely to have any immediate political consequences the investigation may lead to a wider inquiry with potentially broader repercussions.

Netanyahu's government has restricted reporting in Israel on the case, now overshadowing his victory in a national election held last month, using court gag orders, military censorship and direct requests to news editors.

Such steps have done little to douse demands for the authorities to come clean about the circumstances of Zygier's imprisonment and how he was able to kill himself in a highly-supervised isolation cell.

Without citing the case specifically, Netanyahu said on Sunday he "absolutely trusts" Israel's security services and what he described as the independent legal monitoring system under which they operated.

"We are an exemplary democracy," Netanyahu said in remarks aired by Israeli broadcasters.

"But we are also more threatened, more challenged, and therefore we have to ensure the proper operation of our security branches," Netanyahu also said.

"Therefore I ask over everyone: Let the security services continue working quietly so that we can continue to live in safety and tranquility in the State of Israel."

The few Israeli officials who have spoken of Zygier's case have not denied that he was linked to Mossad, which in early 2010 was accused by Dubai of using Australian passport-holders to assassinate a Palestinian arms procurer in the Gulf emirate.

Media reports have speculated that Israel suspected the Melbourne-born Jew of betraying or threatening to divulge Mossad missions, perhaps to Australia's security services, as they probed passport fraud.

Civil liberties groups and some Israeli lawmakers have demanded to know whether Zygier's rights were violated by his months of incarceration under alias.

'Grave charges'
In an apparent reversal from previous statements, Australian Foreign Minister Bob Carr said on Thursday his ministry had known about Zygier's jailing as early as February 2010. On Wednesday he said Australian diplomats in Israel only found out about the detention after his death in custody later that year.

Avigdor Feldman, an Israeli lawyer with whom Zygier consulted in Ayalon prison, said last week that that meeting was arranged by a "Mossad liaison" and that his client had denied "grave charges" for which he awaited trial.

Feldman also said that Zygier's family, which has declined all comment on the affair, knew about his detention. The incarceration was approved by several Israeli courts.

Two senior cabinet members, Intelligence Minister Dan Meridor and Strategic Affairs Minister Moshe Yaalon, told Israeli media on Saturday the case was rare but lawful.

"There are extreme situations...to do with our security and even the need to preserve human life, when we need to take an extreme step such as this," Yaalon told Channel Two television.

Meridor said that publishing the prisoner's identity would have risked "serious harm to security." He did not elaborate.

Tzachi Hanegbi, a lawmaker from Netanyahu's conservative Likud party said he had never been informed of Zygier's arrest as chairman of the parliamentary defence panel at the time.

"This requires explanation," Hanegbi said. "Usually, every significant subject, whether it is impressive achievements or embarrassing failures, is laid out before the subcommittee."

Former Mossad director Danny Yatom told Reuters the agency was under no legal obligation to brief oversight lawmakers in such circumstances.

Related:

Controversy erupts on two continents over Israel's 'Prisoner X'

Israel confirms jailing mystery foreigner

This story was originally published on Sun Feb 17, 2013 8:30 PM EST

Israel broke its official silence on Wednesday over the reported suicide in jail of an Australian immigrant recruited to its spy service Mossad, giving limited details on a closely guarded case.

After appeals by local media chafing at Israeli censorship of a story broken by the Australian Broadcasting Corporation (ABC), a district court near Tel Aviv allowed publication of six paragraphs of sanctioned text - a de-facto preliminary account by the state.

The text said that an Israeli with an unspecified dual nationality had been secretly imprisoned "out of security considerations", only to be found dead in his cell two years ago in what was eventually ruled a suicide.

The district court did not confirm or deny ABC's unsourced findings that the dead man was 34-year-old Ben Zygier, an Australian who moved to Israel and may have been jailed in isolation over suspected misconduct while spying for Mossad.

Social media records showed that Zygier, who died in late 2010 and was buried in Melbourne, had been married with children. His relatives have declined all comment on the case.

The Israeli district court said the unnamed detainee had been held under the supervision "of the most senior officials of the Justice Ministry" and that his family had been informed of his arrest immediately after it took place.

After citing other legal monitoring mechanisms in the case, the district court said: "Beyond this no details can be published about the affair, for reasons of national security."

Prisoner X
Israeli media had earlier quoted the ABC and other foreign reports about Zygier, dubbed "Prisoner X", some of which suggested he had been under investigation by Australia's security services on suspicion of using his native passport for Mossad missions in countries hostile to the Jewish state.

The possibility that a Mossad officer had been treated so harshly drew comparisons to known previous cases when Israel jailed turncoat spies under blanket secrecy, sometimes lasting years.

Israeli intelligence veterans said such measures reduced the risk of enemy countries where the detainees had served learning of their true identities and then tracing their activities in order to expose other spies still under cover.

Mossad is widely reputed to have stepped up its shadow war in recent years against Iran's nuclear program, Lebanon's Hezbollah guerrillas, suspected nuclear procurement by Syria and arms smuggling to Palestinians through Dubai, Sudan and Egypt.

Yet the official secrecy over the Zygier report, reinforced by military censors, caused an outcry in Israel, where reporters noted that their compatriots were but a mouse-click away from learning about the case from foreign media on the internet.

In a highly unusual move within hours of the ABC broadcast, Israeli editors were summoned to an emergency meeting in Prime Minister Benjamin Netanyahu's office on Tuesday and asked not to publish a story "that is very embarrassing to a certain government agency," Israel's liberal Haaretz newspaper reported.

Haaretz ridiculed the gag order as outmoded and counter-productive, but one of the editors who attended the meeting, Yinon Magal of the Walla news-site, was more circumspect.

The explanation he had received for the secrecy, Magal told Israel's Channel 10 television, "persuaded me, overall, that there is a certain logic, albeit small, that there are considerations of national security and of human life here."

Related:

Controversy erupts on two continents over Israel's 'Prisoner X'