Donald Trump’s Department of Justice is examining allegations that Corey Lewandowski used his top position at the Department of Homeland Security for personal financial gain, according to a new report.

The investigation, first reported by The Wall Street Journal, follows a referral from the DHS inspector general and marks a rare instance of Trump’s Justice Department probing an ally.

People familiar with the inquiry said the investigation was focused at least in part on potential contracting fraud. Lewandowski served as a top adviser to then-Homeland Security Secretary Kristi Noem in an unpaid role as a “Special Government Employee” — a designation meant for temporary outside experts — before both were ousted from the department in March following internal disputes and questions over agency spending.

According to sources familiar with the matter, internal investigators examined contracts approved during Noem’s tenure and found that Lewandowski was directly involved in signing specific agreements despite his temporary status.

While at DHS, Lewandowski or close associates approved nearly all department spending decisions over $100,000, giving him broad oversight and influence over agency contractors. Previous reporting by The Wall Street Journal found that Lewandowski appeared to leverage his role by asking several Middle Eastern countries to hire him privately to assist with visa issues and other matters.

During congressional hearings, Noem was probed about accusations of conducting an affair with Lewandowski. Both Noem and Lewandowski have vehemently denied suggestions that they had an affair, with the former previously describing the rumors as “tabloid garbage” at a House hearing. She also described the accusations as a “disgusting lie.”

A representative for Lewandowski said he has not been contacted by the Justice Department and denied any wrongdoing during his voluntary government service.

Lewandowski has also previously denied seeking foreign contracts or influencing DHS contract approvals.

The DHS inspector general’s office declined to confirm or deny the existence of an investigation, though current Homeland Security Secretary Markwayne Mullin has reportedly received briefings on the matter.

Trump addressed the inquiry on Thursday.

“All I know is, I want my people to be honest, and if they’re not going to be honest, they have to be prosecuted,” he said.

Lewandowski, who was Trump’s first campaign manager in 2016, has maintained a long-standing relationship with the president. While Lewandowski reportedly told associates he expected a presidential pardon if charged, his attorney stated that Lewandowski never suggested or spoke about seeking a pardon.

The probe comes as Justice Department officials under the current administration have largely turned their attention to political opponents and pulled back on prosecuting public corruption.

The unit responsible for public integrity investigations has shrunk from approximately two dozen prosecutors to just two following transfers and departures, amid claims from administration officials that public corruption cases have been weaponized for political purposes.