WASHINGTON, June 5 (Xinhua) -- U.S. Air Force Chief of Staff Michael Moseley and Air Force Secretary Michael W. Wynne were forced to resign Thursday.

　　Moseley stepped down after an early morning meeting with Mike Mullen, chairman of the Joint Chiefs of Staff, to discuss a report on the Air Force's problems handling nuclear weapons, the Military Times reported on its web site.

　　Later in the morning, Deputy Defense Secretary Gordon England was dispatched to Wright-Patterson Air Force Base, Ohio, to ask for Wynne's resignation.

　　It is not known who will succeed Moseley and Wynne, but Air Force Vice Chief of Staff Gen. Duncan McNabb will likely become acting chief of staff.

　　The stunning development follows a series of high-profile scandals and disagreements between Air Force leadership and Secretary of Defense Robert Gates in the past year, during which both the Pentagon and congressional leadership have increasingly expressed frustration about the Air Force's top bosses.

　　Wynne became Air Force secretary in November 2005, and Moseley took office in September 2005.

　　Moseley's term expires in September 2009, and Wynne served at the pleasure of the president.

　　While the simultaneous removal of a service's top civilian and uniformed leaders comes as a surprise and is unprecedented, there has been speculation for months among defense insiders that Moseley, Wynne or both could be in trouble.

　　Those troubles include criticism of the Air Force's nuclear weapons handling, two major acquisitions programs that have been stalled by protests, the service's inability to rush more surveillance drones to the war zones and other problems.