U.S. Attorney Marc Krickbaum announced his resignation Thursday, effective the same day.

President Donald Trump appointed Krickbaum as U.S. Attorney for the Southern District of Iowa — which holds court in Davenport, Des Moines and Council Bluffs — in 2017. Before that he worked for nearly a decade as a career federal prosecutor, previously serving as assistant U.S. attorney in Chicago and Des Moines. Krickbaum graduated from the University of Iowa and Harvard Law School.

"During his tenure, the U.S. Attorney’s Office brought significant prosecutions against violent street gangs and others responsible for gun crime, targeted those who sexually exploit children and obtained significant civil settlements against those who commit health care fraud and other fraud against the government," according to a new release from the U.S. Attorney's Office.

Krickbaum, in the release, said, "Serving as United States Attorney has been the privilege of my professional life."

"I am grateful to the law enforcement and agencies we serve with, and to the people of the U.S. Attorney’s Office," Krickbaum said. "They have done great things, and they have many more to come."

The U.S. Attorney's Office would not provide a copy of Krickbaum's resignation letter and had no comment as to the reason for his resignation.

An interim U.S. Attorney was not immediately named but will be appointed until a new attorney is selected by the new administration, according to the U.S. Attorney's Office.

Heads of federal offices commonly change jobs at the end of administrations. Trump's term will end when Democrat President-elect Joe Biden is sworn in on Jan. 20.