Did some of the alleged spies help Israel with its bombing of Lebanon in 2006?
By Jim Muir
BBC News, Beirut
Israel's ability to wage another war against the militant Shia movement Hezbollah may have been compromised by an unprecedented wave of arrests of people in Lebanon alleged to have been spying for the Israelis.
Experts say the arrests appear to add up to a major strategic blow to Israel.
Mobile phone footage circulating in Beirut shows one of the suspected agents being slapped and insulted as he was manhandled out of his house and into the boot of a car.
Lebanese newspapers have reported that more than 40 members of more than a dozen spy networks have been detained so far in a campaign that has gathered pace over the past six weeks, and shows no sign of stopping.
Israel has so far made no public comment on what could be one of its worst-ever intelligence setbacks.
Hassan Nasrallah urged any remaining Israeli spies to turn themselves in
Hardly a day goes by without agents from the Lebanese police, army or general security raiding homes or workplaces in different parts of the country, and taking suspects away.
It could be a butcher or pharmacist in a remote south Lebanese village, a customs official in eastern Baalbek, or a high-ranking army officer from the north.
Several alleged agents who knew they were on the wanted list fled across the border to Israel.
Lebanon has asked the United Nations forces in the south, Unifil, to get them back.
Some of those detained are suspected of providing Israel with information enabling it to strike Hezbollah targets during the 2006 war, which saw dozens of buildings in Beirut's southern suburbs and other parts of the country destroyed by Israeli air or missile strikes.
Others are alleged to have been involved in trying to pinpoint the whereabouts of Hezbollah or other militant leaders past and present, including the current Hezbollah chief, Sheikh Hassan Nasrallah.
Those detained have not been seen since they were taken away, and lawyers have not had access to them.
But details of the allegations and reported confessions have leaked out in Lebanese newspaper reports as interrogations continue at army and police centres.
The net has appeared to spread ever wider and has produced many surprise suspects.
A retired general from the Internal Security Forces, Adib al-Alam, and his wife were among the earlier detentions.
Reports alleged he had confessed to being an Israeli informant for the past 15 years.
Newspapers reported another startling penetration among the most recent arrests - a highly-decorated, twice-wounded Lebanese army colonel from the Christian area of Akkar in northern Lebanon, who commanded the military's Special Forces school.
Another unusual suspect was Ziad al-Homsi, the deputy mayor of Saadnayel, a Sunni town in the eastern Beqaa valley.
The townspeople were stunned and angered by his detention by army intelligence agents in the middle of the night. Mr al-Homsi, 60, was a pillar of his community and a lifelong militant for pan-Arab causes, who had trained at a Soviet military academy.
The walls of his house are adorned with pictures of him as a young fighter battling the Israelis in south Lebanon, including one taken with Yasser Arafat in the Arqoub mountains there as long ago as 1969.
"How can they accuse a man like him, who spent all his history fighting Israel, of working with the Israelis?" asked his daughter Salma.
"My dad is innocent," she insisted. "There is no evidence that proclaims that he is spying for Israel. I think he is a victim of the elections in Lebanon."
Mr al-Homsi was associated with the western-backed, anti-Syrian "14 March" coalition that is fighting to retain its narrow majority in national elections on 7 June.
But the coalition did not take up his cause, and the arrests in general have not become an election issue, because they have been across the board - Sunnis, Shiites, Christians and Palestinians are all among those detained, with no obvious political or sectarian bias.
Lebanese security forces displayed hi-tech communication and surveillance gadgets said to have been found concealed in the homes of some of the suspects.
Explaining the sudden spectacular rash of arrests, Lebanese officials have said that unspecified technological breakthroughs made it all possible.
That may be so. But many unanswered questions remain.
One of the basic principles in setting up espionage networks is that their cells should not be linked in any way, so that the discovery of one does not lead to the kind of wider collapse that seems now to be taking place.
Did the Israelis - who have said nothing to discredit the daily revelations in Beirut - break that fundamental rule?
"Certainly it seems to have been a systemic failure by Israel," said security expert Alastair Crooke, who focuses on Islamic movements.
"Maybe it was a chance find, maybe it was from one person that they interrogated leading to the uncovering of many others, but that in itself would be highly unusual."
Most likely, the arrests were the product of months, perhaps several years, of counter-intelligence work.
Present and vigilant
But by whom? Is it just coincidence that the various different arms of Lebanese security suddenly began making this series of surprise detentions? Or were they being primed by other intelligence services?
Hezbollah's own role remains obscure. Lebanese officials say it has not been involved in the campaign, and it has certainly taken a low and ostensibly passive profile during the revelations.
But Hezbollah is present and vigilant in many of the areas concerned. It also has strong ties with Iran and Syria, whose intelligence services are no slouches.
One Lebanese analyst even went so far as to suggest that events may have come full cycle.
Before the 1979 revolution in Iran, Israel's Mossad was deeply involved in training and advising the Shah's dreaded secret police, Savak - a legacy of expertise inherited by Tehran's current Islamic rulers, who were instrumental in establishing Hezbollah in Lebanon and retain very close ties with the movement.
Whatever the case, the head of Lebanon's Internal Security Forces, Gen. Ashraf Rifi, said the dismantling of so many networks amounted to a strategic blow of the utmost seriousness, unprecedented in the history of the Arab-Israeli conflict.
Other observers agree.
"The loss of these eyes and ears within Lebanon is undoubtedly a major strategic setback for Israel," said intelligence analyst Alastair Crooke.
"Networks of these sorts don't come off the shelf in a supermarket. You can lose them in ten minutes, but they can take 5, 10, 15 years to put in place. So the importance of this should not be underestimated."
Israeli air strikes on Beirut in 2006 destroyed dozens of buildings
In the meantime, Lebanon is left in a psychosis of uncertainty and speculation, with rumours that the arrests could spread higher and deeper into the country's establishment.
The Hezbollah leader, Hassan Nasrallah, has urged remaining Israeli agents or informers to turn themselves in and "rejoin the homeland", in exchange for leniency.
He has also called for the death penalty for those proven to have provided Israel with information that led to the loss of lives and property.
Public consciousness of the affair is so high that it is hard to imagine that remaining Israeli spies would not be either paralysed or preparing to flee the country, if they have not done so already.
In any future confrontation with Hezbollah, the Israelis would want to rely heavily on vital human intelligence.
The indications are that their capabilities in that respect may have been severely compromised.