George Karavetsos, director of the Food and Drug Administration's Office of Criminal Investigations (OCI), will depart the agency to join a private law firm, according to an internal announcement seen by Reuters.

Karavetsos in January 2015 became director of the 280-unit operation, which conducts criminal probes involving food, drugs, devices, cosmetics and tobacco.

His last day will be Jan. 20, the day Donald Trump is sworn in as president.

His departure was announced Tuesday by the FDA's associate commissioner for regulatory affairs, Melinda Plaisier, and Howard Sklamberg, the deputy commissioner for global regulatory operations and policy.

The FDA confirmed the departure, but a spokeswoman declined to comment beyond the announcement.

Karavetsos "has delivered an exceptional body of work, leading noteworthy and important change in OCI," Plaisier and Sklamberg wrote.

The OCI has been under scrutiny in recent months, after Reuters published a series of articles about the office's approach to criminal investigations and controversies surrounding its spending, personnel matters and use of resources.

The U.S. House Energy and Commerce in September launched an examination of the office, asking questions about OCI's case statistics as well as "possible morale concerns with the field offices."

Earlier in September, Reuters reported on concerns by some FDA agents who said OCI managers have forced them to pursue toothless cases involving mislabeled foreign-imported injectable drugs such as Botox, at the expense of cases with more potential to protect the public health.

Reuters also reported that FDA managers in Miami pulled 11 staffers from their usual duties to provide security escorts with emergency lighting for Plaisier and Karavetsos during a March visit to the field office there.

Shortly after the March trip, the FDA approved letting Karavetsos return to his home in Miami where he has run the Maryland-based operation from the agency's Miami field office.

(Reporting by Sarah N. Lynch; Editing by Leslie Adler)