House Oversight Chairman Jason Chaffetz has asked the Department of Justice's Office of the Inspector General to investigate the reason for and information behind FBI Director James Comey's termination.

Chaffetz, who is in Utah on medical leave for the month, sent a letter to Inspector General Michael Horowitz repeating a January request that was never answered.

"I request that you expand the scope of your office's ongoing review of allegations regarding certain actions by the Department of Justice and the FBI in advance of the 2016 election to include the facts and circumstances surrounding the removal of Director Comey.

"You stated previously that your work includes an examination of whether Comey's public communications and notifications to Congress about the Clinton investigation comported with Justice Department and FBI policies and procedures. You separately stated 'if circumstances warrant, the OIG will consider including other issues that may arise during the course of the review.' The recommendation to remove Comey indeed warrants such consideration," Chaffetz wrote.

President Trump cited for his decision to fire Comey the recommendation of Attorney General Jeff Sessions and Deputy Attorney General Rod Rosenstein, who was Comey's immediate overseer.

Chaffetz did not give the 450-employee inspector general's office a deadline.