Australia's Foreign Minister Bob Carr on Monday called for a full explanation from Israel on the circumstances leading up to the death of Australian-born alleged Mossad agent Ben Zygier, known previously as Prisoner X, in an Israeli prison in 2010.

Speaking to reporters in Washington at the end of a week-long visit to the U.S., Carr said that Australia needs answers on the case.

"I'm not aware that there has been a comprehensive accounting for what has happened. What gave rise to his arrest, his detention, his suicide,"  Carr said, according to a report by the Australian Broadcasting Corporation.

The foreign minister also expressed his concern about Australian passports being used by citizens working for intelligence agencies. "That would create risk for all Australians who are travelling," Carr said.

"So Australia's got a clear interest, a distinct point of view on this, an objection to Australian passports being used by dual citizens who are off working for a foreign intelligence agency. We have asked them for all information relevant to Australia on this and we will continue to do that."

In early March, Carr said for the first time that Zygier, who died in a maximum-security Israeli prison, had been working for Israel's government, but stopped short of confirming he worked for the Mossad security service.

The foreign minster ordered an investigation into the case, saying he would ask Israel's government to explain how Zygier managed to kill himself while under tight supervision. His death fueled conspiracy theories in both countries. Israel says it is investigating possible negligence by prison guards.

Earlier this week, Der Spiegel reported that the alleged Mossad agent handed Hezbollah sensitive information that led to the arrest of Lebanese agents in Israel's service.

The German news weekly alleged that before his death in an isolated prison cell, Zygier managed to transfer to Hezbollah the names of two Lebanese agents also operating at the Mossad's behest. The two Lebanese agents, Ziad al-Homsi and Mustafa Ali Awada, were subsequently arrested in May 2009 and sentenced to lengthy prison sentences for espionage.

According to Der Spiegel, Zyiger was recruited into the Mossad in 2003 and assigned to work with European companies doing business in Iran and Syria. But the Israeli intelligence agency wasn't pleased with his work, and in 2007 ordered him to return to Israel. Zygier quit the Mossad in 2008 and went home to his native Melbourne, Australia.

Zygier was arrested in February 2010 and charged with security offenses that have not been made public. A judicial inquiry in Israel found that Zygier hanged himself on December 15, 2010 with a sheet tied to the bars over a window in the bathroom of his cell. The father of two, who immigrated to Israel in the mid-1990s and served in the Israel Defense Forces, was 34 when he died.

ABC in February revealed that the Prisoner X affair involved a dual Australian-Israeli citizen, who it named as Melbourne native Ben Zygier. Israel confirmed Zygier's identity shortly after. Much of the details in Zygier's case remain under gag orders in Israel.