Prisoner X mystery grips Israel

Speculation over the top-secret arrest and suicide of an Australian-Israeli in prison reached fever pitch amid allegations he may have been about to blow the whistle on sensitive Mossad operations.
The mystery surrounding the so-called Prisoner X, identified this week by Australian media as Mossad agent Ben Zygier, has dominated headlines in Israel and Australia despite a media blackout on publishing details about his arrest.
Zygier is believed to have died in December 2010 while in isolation at Ayalon prison in Ramle near Tel Aviv, in a case which Israel went to extreme lengths to cover up.
Late on Wednesday, Israel admitted it had imprisoned a man with dual nationality on security grounds who had committed suicide in jail in 2010, but did not identify him, nor did it confirm reports he worked for its spy agency, Mossad.
But an Israeli lawyer who met Zygier just days before his death confirmed that Mossad agents had been involved in the case, and said he saw no indication the prisoner was planning to kill himself.
According to the Sydney Morning Herald, Australian intelligence officials believe that Zygier may have been about to reveal information about sensitive Mossad operations, including the use of falsified Australian passports, to either Canberra or to the media when he was arrested.
Just a week earlier, Dubai police had publicly accused Mossad agents of carrying out a January hit on a top Hamas militant, saying they were looking for around a dozen people with Western passports -- four of them Australian.
The move sparked a crisis between Israel and several Western governments, including Canberra.
Shortly afterwards, it emerged that Australia's overseas intelligence agency had been investigating Zygier on suspicion of using his passport to spy for Israel, the paper said, indicating he was one of at least three dual Australian-Israelis being probed.