The Department of Homeland Security is reportedly investigating a U.K.-based nonprofit tied to a longtime ally of New York City Mayor Zohran Mamdani over questions surrounding its financial activities, including whether donor money may have reached a U.S.-sanctioned Palestinian organization.

According to the New York Post, federal authorities are examining an organization known as PFF, which reportedly controls roughly $100 million dedicated to supporting anti-Israel initiatives. Investigators are reportedly looking into whether funds connected to the organization were provided to Al-Haq, a Palestinian organization sanctioned by the United States.

“A new fund set up by Arabs across the US, UK, and Australia has been built to take on Israel,” one source familiar with the operation told the Post.

The Post reported that Bassema Yousef, a New York-born Democratic donor who now resides in London, has emerged as a central figure in the organization’s fundraising operation. One source described Yousef as the “lynchpin” of PFF’s fundraising. She has also been identified as a longtime ally of Mamdani.

Yousef has repeatedly posted sharply anti-Israel messages on social media, including accusations that Israel is committing “war crimes with U.S. tax dollars.”

According to sources cited by the Post, Yousef created PFF with financial backing from two wealthy businessmen: Basil Qunibi, an investment executive based in Austin, Texas, and Yasser Shahin, a Palestinian-Australian motorsports magnate.

British corporate records confirm Shahin’s involvement in supporting PFF, according to the report. The IRS has also confirmed that the organization maintains a nonprofit entity registered in Delaware.

People described as having direct knowledge of PFF’s activities told the Post that the organization’s leadership provides funding for anti-Israel messaging and works to defend pro-Palestinian activists.

“PFF is a strategic foundation that is large, well-funded, and institutional in quality,” the foundation says on its website. “We partner with organisations that we believe have an ability to consistently deliver results that align with our strategic objectives.”

The organization has also publicly rejected suggestions that its work supports violence.

“PFF and its partners are unequivocally committed to justice, peace, inclusion and non-violence,” the nonprofit said.

DHS did not immediately provide Fox News Digital with a response regarding the report and declined to discuss the matter when contacted by the Post.

“HSI does not comment on the existence or status of specific investigations, nor on investigative methods, intelligence sources, or potential enforcement actions,” a DHS spokesperson told The Post, referring to the Homeland Security Investigations unit.

The Post emphasized that the existence of the reported federal investigation does not itself establish that PFF, Yousef, Mamdani or anyone else connected to the organization engaged in criminal wrongdoing.