Investigators suspect that the theft of classified intelligence documents from an Israel Defense Forces database and the transfer of those files to people in the Prime Minister’s Office was “systematic,” and the publication of one such document in foreign media is a source of “ongoing” danger to the lives of both soldiers and hostages in Gaza, according to a Monday report.

Citing an unnamed source involved in the investigation, Channel 12 news said that a September report in Germany’s Bild newspaper damaged Israel’s intelligence capabilities, including the “exposure of sources.”

“The use of the published material caused real and ongoing security harm that, daily, endangers the safety and security of IDF soldiers at war and harmed and harms the capacity to protect the lives of the hostages in the negotiations for their release,” the source was quoted as saying.

The report said that while the illicit extraction of sensitive documents from the IDF’s databases was bad enough, their publication revealed some of Israel’s sources of information to its enemies. The material was barred from publication in Israel by the military censor.

Both the defense establishment and investigators in the case share the assessment that the exposure of the material — as was the case with the Bild article — harmed efforts to free the hostages, the report said.

This ongoing danger to soldiers and to the efforts to free the hostages “is the heart of the matter,” according to the report, which said the questions of what the suspects intended to do with the material, who knew what they were doing, and who gave the instructions were all being probed.

The report came after another IDF officer was arrested on Monday as part of the investigation, bringing the total number of suspects in the case to five.

According to Hebrew media outlets, the four IDF soldiers arrested for leaking documents through the Prime Minister’s Office all serve in an intelligence unit tasked with preventing leaks.

The same unit was initially tasked with investigating the leaks to foreign media, according to Haaretz, but the investigation was later transferred to the Shin Bet.

The leaked material was not found by IDF soldiers in Gaza, the Kan public broadcaster reported on Monday, but was uncovered through “another type of intelligence.”

One of four soldiers previously arrested in the case was released on Sunday, according to Haaretz.

Eli Feldstein, a spokesman for Prime Minister Benjamin Netanyahu and the central suspect in the case, was arrested in an early-morning police raid last Sunday on suspicion of divulging top-secret information with national security implications to European media outlets, including Bild.

Hebrew media reported on Monday that Feldstein and another suspect in the case were allowed to meet with their lawyers for the first time since their arrests.

Because the pair are suspected of having committed a national security offense, they had been barred from meeting with an attorney.

The names of the other suspects remain under gag order.

The leaked Hamas document said to have formed the basis of the Bild article appeared to show that the Palestinian terror group was drawing out hostage talks as a form of psychological warfare against Israel, including the use of pressure on the families of the hostages.

According to sources quoted in Hebrew media, the document was penned by Hamas military intelligence, not the group’s then-leader Yahya Sinwar, who was since killed by Israeli troops in Gaza. The Monday report said that the document was inaccurately represented both in the Bild article and in Netanyahu’s subsequent references to it, so as to imply that Sinwar had penned it.

A second, widely discredited article in the London-based Jewish Chronicle also in early September — which was later withdrawn — claimed a document uncovered by the IDF in Gaza showed that Sinwar had planned to spirit hostages out of Gaza through Egypt.

At the time, IDF spokesman Daniel Hagari officially denied that the army had any knowledge of the supposed intelligence on which the Chronicle story was based, while defense officials described the claims as likely baseless.

Both articles were published days after the bodies of six hostages were found in a tunnel in southern Gaza’s Rafah. According to the IDF, the six were found with signs of violence showing they had been executed a day or two earlier, as troops closed in on the location.

The discovery heightened doubts about the wisdom of relying on rescue operations to save hostages and reenergized protests pressuring the government to seal a deal to free the remaining living captives, even if it meant halting the military offensive.

The Monday Channel 12 report quoted another source elaborating: “This is not a case [merely] about leaks. This investigation was opened after the leak of secret, classified material was identified, which was likely to burn sources. This is sensitive intelligence material that was taken from the IDF, extracted illicitly, and manipulative and dangerous use was made of it.”

The document allegedly leaked to Bild “was not the only document” taken and conveyed to “people in Netanyahu’s office,” according to the report, which said that there were “apparently other classified documents” that were accessed and conveyed in this way.

The ongoing investigation, which involves the police, IDF and Shin Bet, is said to be focused on “grave leaks of classified information from the IDF’s Intelligence Directorate to unauthorized recipients.”

According to Channel 12, the Shin Bet suspects that an “infrastructure” was put in place that was able to access “all the classified material held by Military Intelligence” and that “it extracted — and may have intended to continue to extract in the future — classified material that could expose the capabilities of the entire intelligence community.”

The Rishon Lezion Magistrate’s Court said in a ruling on Sunday that the leaks in the case were alleged to have risked efforts to secure the release of the 97 hostages kidnapped by Hamas-led terrorists on October 7, 2023, who remain in the Strip, many of them still alive.

The case is being taken so seriously by prosecutors, in part because it risked revealing to Hamas key intelligence-collection methods.

Critics have noted that the Bild and Jewish Chronicle reports dovetailed neatly with Netanyahu’s talking points at the time, which sought to play up the importance of Israel’s demand for soldiers to remain stationed inside Gaza while placing blame on Hamas for the lack of progress on a hostage-ceasefire deal.

Netanyahu is not thought to be a suspect in the affair and no evidence of a direct connection has been presented.

The Prime Minister’s Office has distanced itself from Feldstein, though multiple outlets have reported that he functioned as a PMO employee in all but name over the past year and was frequently in the premier’s close orbit. He has been seen beside Netanyahu in various photos over the past year and was said to have been in close contact with the premier.

The Ynet news outlet reported on Sunday that investigators were examining four separate issues in the case: the leaking of top-secret documents; allowing an adviser without security clearance to access meetings and premises that should have been off-limits to him; negligence in the handling of classified documents; and the use of documents to influence public opinion on a hostage deal.

Some of the suspects in the ongoing investigation could reportedly face up to 15 years in prison.

Meanwhile, during the probe, Netanyahu sent a letter to Attorney General Gali Baharav-Miara, asking her to investigate separate leaks from cabinet meetings throughout the war.

“Since the beginning of the war,” he wrote, “we have witnessed a never-ending flood of serious leaks and revealing state secrets.”

Netanyahu added that the leaks have come from cabinet meetings, the national security cabinet, hostage negotiators, and other means, in situations at which there were no government members present.

“Until now,” he wrote, “despite my repeated requests that these leaks be investigated and an end be put to them, nothing has been done.”

He claimed that Shin Bet chief Ronen Bar told him on Saturday that there must be an official request for an investigation, and included a secret annex listing leaks that he said have not been investigated.

Part of the PMO’s defense around the ongoing investigation has been that while other leaks were not investigated, those that could harm the prime minister were being investigated aggressively.