The Air Force has fired nine commanders in the wake of a scandal involving cheating on tests related to the U.S. nuclear missile program, that military branch's top official said Thursday.

The fired officers were in "leadership positions" at Malmstrom Air Force Base in Montana, Air Force Secretary Deborah Lee James said. Though not directly involved in cheating, they failed to provide adequate oversight of their crews, according to James.

A 10th commander submitted his resignation and will retire.

Some of those involved are accused of cheating on the test via text messaging last summer, while others are accused of not speaking up about it.