A former D.C. employee pleaded guilty to a bribery charge in federal court Thursday, admitting that he accepted cash kickbacks and sexual favors from welfare recipients in exchange for nearly $1.5 million in fraudulent assistance payments.

Demetrius McMillan, 48, worked 13 years at the D.C. Department of Human Services (DHS), city officials said. However, the criminal conduct for which he was charged took place only last year, according to court documents.

Human Services Director Laura Zeilinger denounced McMillan’s actions in an interview Thursday and said they were not representative of the agency.

“It literally makes me feel sick at the pit of my stomach,” she said.

McMillan declined to comment after his appearance Thursday in U.S. District Court for the District of Columbia. His attorney, Thomas Abbenante, said McMillan was contrite and had cooperated with the investigation.

“Mr. McMillan is very sorry for what he did in this case,” Abbenante said. “He admitted his guilt at the first opportunity.”

The charge against McMillan was first reported by NBC4.

McMillan’s plea marked the second time in two weeks that employee fraud at DHS has come to light. In late February, another former worker at the agency, Gary T. Holliday, pleaded guilty to a federal wire fraud charge after fraudulently diverting more than $400,000 in welfare money.

In a brief interview after Thursday’s court hearing, D.C. Inspector General Daniel W. Lucas — whose office worked on the case with the office of U.S. Attorney Jessie K. Liu, the Federal Bureau of Investigation and the inspector general for the U.S. Department of Health and Human Services — said the McMillan and Holliday cases were part of a single, ongoing investigation.

Lucas declined to say whether additional charges might be brought. It was unclear whether any of those who received fraudulent payments from McMillan would be held criminally liable.

Zeilinger said that she believed no other DHS employees would be charged as a result of the investigation. She also said that new safeguards have been put in place to prevent the fraudulent diversion of welfare funds.

Under federal sentencing guidelines, McMillan faces a likely range of nine to 11 years in prison. He is scheduled to be sentenced in June, and has also agreed to pay $1.46 million in restitution.

Holliday, who could face more than three years in prison, is also scheduled to be sentenced in June.

Both Holliday and McMillan took advantage of a bureaucratic process, known as “underpayments,” in which social-services workers could authorize up to $2,000 in payment adjustments for clients enrolled in the Temporary Assistance for Needy Families (TANF) program or Supplemental Nutrition Assistance Program (SNAP), known as food stamps.

According to court documents, Holliday set up a false account for a welfare recipient and then made more than $400,000 in TANF payments to the benefit card attached to the account, which he then accessed.

McMillan was engaged in a far-ranging scheme that offered fraudulent benefits to hundreds of D.C. residents, authorities said.

Between April and July 2018, McMillan made 779 fraudulent assistance payments to approximately 305 beneficiaries, officials said. Of those, 296 were women. McMillan exchanged text messages of a sexual nature with 50 of those recipients, authorities said, soliciting sexual favors as recompense for fraudulent payments.

He acknowledged in his plea agreement that he accepted sexual favors from 10 to 20 female beneficiaries. He also solicited more than $380,000 in cash kickbacks from those who received his payments, and accepted at least $150,000, officials said.

McMillan — a heavyset man with a graying beard and dark-rimmed glasses — said little during his court appearance. He stood and answered a string of yes-or-no questions as Judge Paul L. Friedman walked him through the details of his plea agreement.

At one point Friedman paused and stared at him.

“Do you need to sit down for a minute?”

“I’m okay, sir,” McMillan replied.

Fenit Nirappil contributed to this report.