Prisoner X
Prisoner XScreen Shot

Israel's mysterious Prisoner X, believed to be an Australian citizen named Ben Zygier who allegedly committed suicide in an Israeli prison in 2010, was under investigation by the Australian Security Intelligence Organization (ASIO), an Australian newspaper revealed on Wednesday.

According to the report, ASIO had suspected Zygier of using his Australian passport to spy for Israel.

Zygier reportedly reacted angrily when Australia’s Fairfax Media confronted him in early 2010 with allegations that he was working for the Mossad.

He reported expressed shock at the suggestion he was under any kind of surveillance and said that he had also changed his name for personal reasons.

''I have never been to any of those countries that you say I have been to,'' Zygier told Fairfax Media, according to Wednesday's report. ''I am not involved in any kind of spying. That is ridiculous.''

On Wednesday, the District Court in Lod removed the gag order on an investigation into the Prisoner X affair.

The story of the so-called Prisoner X first surfaced in May 2010 when Israel's Ynet news ran a story in which it alleged that a prisoner was being held in top-secret conditions, whose identity and crime were not known even to his jailers. The story, however, was quickly taken offline due to an Israeli government gag order.

A court ruled on Wednesday evening that media outlets may reveal that there was indeed an Israeli citizen, who held foreign citizenship as well, who was held in an Israeli prison under a false name.

The prisoner was given a false name for security reasons.

While the prisoner was given a false identity while in jail, his real family had been informed of his whereabouts. He also had lawyers – attorneys Roi Belhar and Boaz Ben-Tzur – who were aware of his situation.

The prisoner “was found dead in his cell two years ago,” state sources indicated. “One and a half months ago an investigation concluded that the death was a suicide.”

“The file was passed to the state prosecution to determine if there had been criminal negligence.”

Further details of the case remain under wraps due to security concerns.

Australian media outlets began reporting on the Prisoner X affair two days ago. Reporters managed to find the prisoner's parents, who confirmed that "Prisoner X" was their son but declined to speak about his death, saying it was too painful to discuss.

The gag order was removed in Israel after three Knesset Members exposed the Prisoner X affair in the Knesset plenum, thus using their parliamentary immunity to circumvent the gag order.

The three - MK Dov Khenin (Hadash), MK Zehava Galon (Meretz) and MK Ahmed Tibi (Raam-Taal) - grilled outgoing Justice Minister Yaakov Neeman over the rumored suicide on Tuesday.

MK Miri Regev (Likud / Yisrael Beytenu) asked the Attorney General and the Knesset Officer to immediately launch an investigation against the three and remove their immunity.

"MKs cannot be above the law," Regev wrote on her Facebook page. She added that she asked the Attorney General to find out how the Prisoner X affair was leaked to the MKs. "I also asked him to check why the MKs violated the gag order."

"This is not a matter of stifling speech," she added, "but an attempt to preserve state security in an era of advanced communications and technology."