U.S. Defense Secretary Ash Carter fired his top military aide Thursday after he learned about "allegations of misconduct" against Lieutenant General Ron Lewis.
Carter issued a brief statement saying he had turned over the matter to the Pentagon inspector general for investigation, and that he had confidence in the inspector's ability to determine the facts.
There was no information available about what Lewis was accused of doing. A Pentagon official said Carter was presented with the allegations Tuesday and was taken by surprise.
"I expect the highest possible standards of conduct from the men and women in this department, particularly from those serving in the most senior positions," Carter said. "There is no exception."
Lewis is a three-star general who served three tours of duty as a commander and attack helicopter pilot in Iraq and Afghanistan.