A senior official at the Department of Homeland Security was being investigated for potential involvement in drug trafficking, according to new court files unsealed Tuesday.

The revelation came in a case in which authorities charged the official, Serina Baker Hill, with bilking the government out of thousands of dollars in disaster relief money for a home she claimed was made unlivable because of flooding.

Court documents show agents detected the disaster scam while listening to wiretap conversations between Ms. Hill and her husband, Maurice Hill, whom they suspected of drug trafficking. They were monitoring Ms. Hill’s communications too because of her role as director of Customs and Border Protection’s Center for Excellence and Expertise over Automotive and Aerospace Engineering.

“During the course of the investigations, it was discovered that both HILL and Maurice had engaged in a scheme to defraud FEMA after flooding occurred in Detroit, Michigan on August 24, 2023,” wrote FBI Special Agent Andrew J. Matas.

When agents confronted Ms. Hill in a 2024 interview, she lied to them, Mr. Matas said.

FBI Director Kash Patel celebrated the case on social media.

“This is part of the new FBI’s renewed efforts to crack down on public corruption and deliver accountability for the American people,” he wrote. “Justice will be done.”

Ms. Hill is charged with lying, wire fraud, disaster fraud and making false statements to the government. That latter charge stems from her denying that she had never defrauded the government.

In the court documents, Mr. Matas said the FBI has been probing Mr. Hill for drug trafficking and “other offenses.” That’s why they were monitoring his phone and electronic communications.

“Maurice is married to Serina Baker Hill. Due to Hill’s employment as the Director of United States Customs and Border Protection’s (CBP) Center for Excellence and Expertise over Automotive and Aerospace Engineering, a concurrent investigation was opened by your affiant to investigate her involvement with Maurice’s narcotics trafficking and Hill was listed as an interceptee on the wiretap application and order,” the agent wrote.

The couple submitted disaster claims for two Detroit homes last year. The FBI said one, filed by Mr. Hill, was quickly flagged as fraud because it wasn’t their primary residence.

Ms. Hill’s application, submitted on what was their primary residence, drew a Federal Emergency Management Agency inspector visit. Ms. Hill said she didn’t feel safe living in the home while the basement was repaired.

Two days later she was approved for $3,125 in repairs and $3,190 to pay for two months of rental assistance.

The money was deposited that day, and the FBI said it then caught the couple talking on the phone where Mr. Hill joked about buying “some Guccis” with the money.

“They probably want you to fix something,” he told Ms. Hill.

“Is that how it works?” she replied.

In another conversation that day, they talked about fabricating a letter from an inspector to try to get more money from FEMA for repairs.

“We don’t want it to be okay. We want them to have issues,” Ms. Hill said.

No lawyer was listed in court files Wednesday for Ms. Hill.

CBP said Ms. Hill wasn’t a sworn law enforcement officer. She had been placed on unpaid leave pending the outcome of her case.