A forum campaigning for the release of Israeli hostages called for a probe into an alleged leak of secret documents by an aide to Prime Minister Benjamin Netanyahu, which may have sabotaged efforts to release them.
An Israeli court announced on Sunday that Eliezer Feldstein, a former aide to Netanyahu, had been detained along with three others for allegedly leaking documents to foreign media.
The case has prompted the opposition to question whether Netanyahu was involved in the leak – an allegation denied by his office.
"The (hostage) families demand an investigation against all those suspected of sabotage and undermining state security," the Hostages and Missing Families Forum said in a statement.
The forum represents most of the families of the 97 hostages still held in Gaza after they were seized on Oct. 7.
"The suspicions suggest that individuals associated with the prime minister acted to carry out one of the greatest frauds in the country's history," the forum said.
"This is a moral low point like no other. It is a severe blow to the remaining trust between the government and its citizens."
Critics have long accused Netanyahu of stalling in truce negotiations and prolonging the war to appease his far-right coalition partners.
Israel's Shin Bet internal security agency arrested four people, including Netanyahu's aide, in connection with a case involving the leaking of security documents from his office, the Israeli Broadcasting Authority said Sunday.
On Friday, Israel's Haaretz daily reported that an aide in Netanyahu's office leaked information and documents to foreign newspapers, some of which contained outright lies and others sensitive security information.
The broadcasting authority said late Sunday that after a court in Rishon LeTsiyon lifted a publication ban, it was allowed to disclose the arrest of four individuals in the security leak case.
The main suspect is Eliezer Feldstein, a Netanyahu aide, whose detention has been extended.
Among those arrested is also an advisor to Netanyahu, although the agency did not name them.
A memo issued by the court said "the investigation into the leak case began after significant suspicion arose at Shabak (Shin Bet) and the military regarding the leaking of sensitive and secret intelligence information from military systems and its illegal disclosure."
The broadcasting authority reported that the leaks from Netanyahu's office raised security concerns about "the potential negative impact on Israel's security and efforts to secure the release of captives in Gaza."
Israeli opposition leaders Yair Lapid and Benny Gantz exploited the leak scandal to launch an attack on Netanyahu's government, which they have been calling on to resign for months.
In a joint news conference, Lapid and Gantz said what occurred was "not a suspected leak, but the disclosure of state secrets for political purposes."
They asserted that "what has been allowed to be published in the context of the security case is enough to destabilize the foundations of the state."
Recently, the U.S. news portal Axios said the scandal involves the leaking of political, security and military documents to the German magazine Bild.