Behind Israel's "humanitarian gesture" in freeing the ailing Hamas leader, Sheikh Ahmed Yassin, from a prison hospital, and having him helicoptered to Jordan early yesterday lies a saga of espionage, violence and diplomatic crisis that is extraordinary even by the Byzantine standards of the Middle East.

Not all of its details have yet emerged; and some confusion still surrounds much of what is known. But at the root of it, there seems little doubt, was a botched attempt by Israel to assassinate a leading Hamas activist in Amman. The ripples of that abortive operation threatened to destabilise King Hussein's regime, to rupture the three-year-old peace treaty between Jordan and Israel, and to prompt an intensification of Hamas's murderous attacks inside Israel.

The release of Sheikh Yassin, engineered, according to some reports, after the personal involvement of President Clinton, represented Israel's desperate attempt to avert those disastrous repercussions. It may have succeeded, but the affair is not over.

The story begins last Thursday, when Khaled Mashaal, the head of the Hamas political bureau in Amman, was allegedly attacked by two men of western appearance as he made his way with his three children to his office in the Jordanian capital. His assailants are said to have sprayed nerve gas into his face, and possibly to have injected him with some kind of chemical. The pair escaped in a rented car, but Mr Mashaal's bodyguard, Muhammad Abu-Saif, gave chase, and when they tried to switch cars a few kilometres away, Mr Abu-Saif intercepted them, alerted passers-by, and managed to hold them until Jordanian police arrived.

The attackers were carrying Canadian passports but, while Israel is naturally disinclined to acknowledge this, King Hussein has indicated that they were working for the Mossad, the Israeli secret service. Their mission, which may have required the personal approval of the Prime Minister, Benjamin Netanyahu: to eliminate Mr Mashaal, presumably perceived by Israel as a key figure behind the Hamas suicide bombings.

Such a Mossad assassination plot is by no means unprecedented: two years ago, for instance, Fathi Shikaki, the head of the Hamas splinter organisation, Islamic Jihad, was gunned down in broad daylight outside a hotel in Malta - a killing for which Israel has never denied responsibility.

No sooner had Mr Mashaal been attacked than Hamas was blaming Israel and threatening revenge. The official Israeli response was a blithe no comment. But King Hussein, monitoring his security forces' investigation of the incident, quickly realised the Mossad was to blame and telephoned Mr Netanyahu to read him the riot act. The king would doubtless have castigated Mr Netanyahu for infringing Jordanian sovereignty by sending hit-men to his capital.

Certainly, Jordan's Islamic opposition politicians, already calling for the abrogation of the 1994 Jordan-Israel peace treaty because of the disintegration of the peace process, would have a field day.

The king's first demand of Mr Netanyahu was that Israel supply the antidote to the chemical poisons threatening Mr Mashaal's life. Were the Hamas leader to die, the king may well have pointed out, Jordan would have little choice but to put on trial and possibly execute the two captured Israeli agents, a turn of events with dire implications for bilateral relations.

Mr Netanyahu got the message. In the course of various secretive trips to and from Amman in recent days, reportedly involving the king's brother Crown Prince Hassan, Israeli Minister Ariel Sharon, and the Israeli cabinet secretary Danny Naveh, the antidote was provided, Mr Mashaal's condition improved dramatically, and preparations were laid for the next phase of the damage-limitation operation: the release of Sheikh Yassin.

The 61-year-old founder and spiritual leader of Hamas, jailed by Israel in 1989 for allegedly inciting his followers to carry out murderous attacks on Israeli targets, has been in extremely poor health for two years.

Israeli security officials have long been pressing for his release, concerned that his death in jail would prompt a massive campaign of Hamas violence. But until this week, Mr Netanyahu resisted, fearing Hamas would be boosted by the freeing of a man who, though blind, and paralysed from the neck down, remains the key Islamic figure in Gaza - a religious counterpoint to the secular Yasser Arafat.

It was King Hussein who insisted on his release now - as a means of deflecting Hamas opposition to his regime after the assassination attempt. Israel Radio has reported the sheikh may also have been freed as a possible piece in an exchange deal that might see the two captured Mossad men deported to Israel.

And so, in the dead of night, the grey-bearded sheikh was taken from his prison hospital, his skeletal form covered in a brown-check blanket, laid on a stretcher, and flown by Jordanian helicopter to Amman. It was a measure of his concern at the potential implications of this affair that the king met the sheikh's helicopter, to welcome into his country a man whose loyal supporters are among the most fervent critics of his regime.

Initially believing the sheikh to have been forcibly exiled by Israel, Hamas leaders in Gaza yesterday morning began planning protest marches and talking of new bombing attacks. Later, though, the king contacted the Hamas leadership and made clear that the sheikh was in Amman for hospital treatment only, and was free to return to Gaza. Israel has not confirmed this. Nor indeed is Israel yet commenting on another claim by Hamas, that one of its leaders in Gaza, Ibrahim Makadmeh, is being held by the Israeli security forces.

Israel is today celebrating the Jewish new year, a time to reflect on the disappointments and failures of the previous year, and to hope for a better period ahead. Mr Netanyahu will want to put this latest fiasco behind him as quickly as possible.

King Hussein, too, will be hoping that the worst of this affair is over, and that his role in securing the release of Sheikh Yassin will spare him the ire of the Islamic militants.

What the king may privately wish for Mr Netanyahu in the new year, after that botched Mossad hit in his capital city last week, probably does not bear printing.

(David Horovitz is the managing editor of the Jerusalem Report)

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