WASHINGTON — A US government watchdog has found at least four more staffers for the United Nations’ Palestinian refugee aid agency “kidnapped” Israelis and aided Hamas’ terror attack on Oct. 7, 2023, information that is likely to feed into a federal criminal probe, sources told The Post.

The USAID Office of Inspector General, in an April 30 investigative summary, cited “four additional current or former staff” at the UN Relief and Works Agency for Palestine Refugees, three of whom were teachers and one of whom was a social worker.

All were “alleged to have participated in the holding of civilian hostages kidnapped from Israel and/or the terrorist activities in Israel on October 7, 2023,” the summary stated.

More than 100 UNRWA officials are being investigated by the IG’s office — with evidence now supporting at least 21 were affiliated with Hamas or participated in the terror group’s massacre of 1,200 in the Jewish state, including 46 US citizens. More than 250 hostages were also taken back to the Gaza Strip.

“The recent investigation by the USAID IG confirms that the UN is deficient in vetting its own staff for ties to terrorist organizations,” a senior State Department official told The Post.

“As the UN itself doesn’t consider Hamas a terrorist organization, both UN agencies and local NGOs [non-governmental organizations] may still hire Hamas-affiliated staff that place programs at high risk for diversion. This will not be tolerated.”

All 21 UNRWA staffers have since been proposed for suspension or debarment from receiving federal funds for the next decade. Past USAID OIG reports have called out the risk of hundreds of millions of dollars in US taxpayer funding to the UN agency being diverted to terror groups.

In response to the IG probe’s findings, Department of Justice senior counsel Leo Terrell also posted on X of the four most recent employees flagged for Hamas ties: “Jail them!”

The DOJ and FBI have already been looking into allegations that UNRWA employees assisted Hamas, according to two sources familiar with the matter. One of those people noted that USAID OIG’s evidence could be forwarded eventually to prosecutors should they decide to bring a case.

“The FBI is definitely involved in it on the counterterrorism side,” the other source noted, adding that “the murder of Americans” in Israel had prompted their involvement.

UNRWA had already faced a civil suit that alleged it “aided and abetted” Hamas by providing more than $1 billion to Gaza, but a Manhattan federal judge ruled last October that the agency has immunity from such legal claims since it is part of the United Nations.

President Trump’s DOJ had moved to strip UNRWA of that immunity in April 2025 — and has since appealed US District Judge Analisa Torres’ decision to the Second US Circuit Court of Appeals.

“The question of immunity for UNRWA,” one source also noted, “would also be relevant for criminal indictments and economic sanctions.”

The DOJ announced charges in September 2024 against senior Hamas leaders, including providing material support for a US-designated terror organization that has killed Americans and conspiring to bomb locations or use weapons of mass destruction in killings — all of which carry a maximum penalty of life in prison or the death penalty.

Those charges or other counts for financing terrorism or evading sanctions in violation the International Emergency Economic Powers Act — both of which carry maximum penalties of 20 years in prison each — could be brought against individuals who conspired with Hamas, sources said.

Trump signed an executive order in February 2025 halting all US funding to UNRWA, which had received up to $1.5 billion during the Biden administration.

As of last month, congressional appropriators are also looking at cutting total UN funding by up to $1.8 billion — with a provision specifically eliminating American tax dollars from going to any group that doesn’t cooperate with the USAID OIG investigation.

UNRWA got more than $839 million in funding through the United Nations in the 2025 calendar year, and the UN is asking for billions more this year as part of a $71.4 billion package for recovery and reconstruction in Gaza.

One month before the funding request, USAID OIG had uncovered an UNRWA school principal, Hafez Mousa Mohammed Mousa, who served as an operative in Hamas’ East Jabaliya Battalion and helped with coordinating communications for the Oct. 7 attack.

The IG’s probe led to the debarment of Mousa from receiving federal funds for the next 10 years — the first time a terrorist affiliated with UNRWA had been prevented from receiving humanitarian assistance.

Mousa is the only individual who has been named so far as part of the investigation. A senior US diplomat said following his debarment that the “list” of UNRWA officials under investigation was “expanding.”

Reps for the DOJ, FBI and UNRWA did not respond to requests for comment.