A former spokesman for Israeli Prime Minister Benjamin Netanyahu has been arrested on suspicion of leaking classified military documents to the press without authorization, possibly damaging the chances of a deal to free hostages being held in the Gaza Strip, an Israeli court said Sunday.

Four people, three members of the Israeli security apparatus and Eliezer Feldstein, the former associate of Mr. Netanyahu, have been detained, a court in Rishon LeZion (center) clarified.

An investigation is underway by the Shin Bet (counterintelligence) and the military following the publication in September of articles based on confidential military documents in two newspapers, London’s Jewish Chronicle and Germany’s Bild tabloid.

One referred to an alleged plan by Yahya Sinwar, a political leader of Hamas, to sneak out of the Gaza Strip with hostages to Egypt via the “Philadelphia Corridor”, a zone on the Palestinian enclave’s southern border with Egyptian territory . The other was based on notes presented as coming from the Hamas leadership about its leader’s strategy to obstruct negotiations for the release of the hostages.

That information, which was at least partially proven to be false, according to the court, “damaged the ability of the security services to achieve the goal of freeing the abductees,” it said, while also calling for much of the investigation to be censored.

Opponents of Mr. Netanyahu suspect that the prime minister used the leaks to refuse to relinquish control of the Philadelphia corridor, which has been and remains a major obstacle in indirect negotiations with Hamas, deadlocked since the summer.

“According to the investigation, associates of Mr. Netanyahu leaked confidential documents and falsified documents to undermine a possible (deal to) release the hostages,” opposition leader Yair Lapid stressed during a press conference.

“If Netanyahu knew, he is complicit in one of the most serious security breaches in (Israel’s) history. If he didn’t know, then what does he know?” he snapped.

Mr Netanyahu rejected the accusations on Friday, asserting in a statement that the document relied on by Bild had never “reached” his office. Without mentioning Mr. Feldstein’s name, he also emphasized that his former colleague “never participated in meetings about security issues,” nor was he cleared to handle classified documents.