Shin Bet chief David Zini has, for the first time, publicly addressed rapidly spreading conspiracy theories suggesting that intelligence officials were complicit in the October 7 attacks.
The claims, which claim that Hamas was assisted by members of the security establishment, have been spreading unchecked on social media in Israel.
They have become particularly popular among hardline supporters of Prime Minister Netanyahu, who see them as proof that he was not at fault for the national security failings in the lead-up to the massacre.
An investigation carried out by the Shin Bet under previous director Ronen Bar, whom Netanyahu sacked after a long-running political feud partly fuelled by trading blame for the attacks, found no evidence of any such wrongdoing.
Speaking on Tuesday to a conference attended by various leading intelligence figures, Zini said he accepted the findings of that report, though he stressed that there are "still additional issues to examine".
Nonetheless, he insisted: "There was no ‘betrayal’ or ‘collaboration’ on the part of the Shin Bet or any members of the security establishment.
"[Shin Bet] committed a severe professional failure, and we must work day by day, hour by hour, in order to correct and implement all the lessons, and complete what remains to be investigated."
Netanyahu has not addressed the claims publicly, but reportedly told a private meeting of the Knesset Foreign Affairs and Defence Committee this month that "there was a serious intelligence failure, but there was no treason".
It comes as the coalition government continues to rail against calls for an independent state commission of inquiry into the political and security failures running up to October 7.
Despite support from prominent groups representing the families of the victims, ministers have resisted the prospect of a state commission, first arguing that such an inquiry could not take place while Israel was at war, and later claiming, as several cabinet ministers alleged, that Supreme Court President Isaac Amit could not be trusted to appoint an impartial chair for the panel.
Instead, the government has proposed a government commission, whose members would be appointed by ministers and whose remit will be determined by a committee chaired by Netanyahu himself.
The prime minister suggested in December that the inquiry should examine the impact of the 1993 Oslo Accords, the 2005 disengagement from Gaza, and the anti-judicial reform protest movement in 2023.
All of those have been the subject of heavy criticism from the coalition and Netanyahu's Likud party.
Opposition Leader Yair Lapid condemned the decision, saying: "Those directly responsible for the disaster will appoint a cover-up commission whose sole purpose is to clear them of guilt. It will not help them. They are guilty.
"This committee is not meant to investigate the truth; it is meant to bury the truth. Politicians will control it, and its goal is to pollute the testimonies, destroy evidence, mislead, and confuse the public."
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