The United States Marshals Service, which has come under criticism in some congressional quarters, is losing its director to retirement, federal officials said Tuesday. 

Stacia Hylton has served since January 2011 as director of the agency, whose responsibilities include protecting federal courthouses, transporting prisoners and capturing fugitives. 

The Marshals Service announced her departure on Tuesday, saying she expects to work on community policing and law enforcement safety and spend time in her retirement house in South Carolina. 

"Stacia Hylton is a dedicated public servant, a devoted law enforcement officer, and a champion of fair and effective criminal justice," Attorney General Loretta Lynch said in a statement. The Marshals Service is a component of the Justice Department. 

The announcement comes as the Marshals Service has attracted the scrutiny in recent months of lawmakers concerned about its hiring and spending practices. The Marshals Service said she had already been planning to retire since the winter. 

Sen. Chuck Grassley, an Iowa Republican and chairman of the Judiciary Committee, gave a floor statement last month citing "serious questions" about the agency's leadership, including allegations of nepotism, punishment of whistleblowers and potential mishandling of money from its asset forfeiture fund. 

The Justice Department has referred allegations of misconduct to its inspector general. 

"As the Marshals Service moves forward, the next director must be committed to bringing real, positive change to what appears to be a culture corroded by unethical hiring practices, misuse of funds and retaliation against whistleblowers," Grassley said in a statement Tuesday.