An unnamed CBS News/National Journal reporter traveling aboard Mitt Romney's campaign plane yesterday happened across a loaded gun left unattended inside the plane's bathroom by a Secret Service agent.

The plane was en route from Tampa to Indianapolis, where Romney was due to speak. The reporter informed another agent of the stray weapon, and it was subsequently retrieved.

Though the GOP presidential nominee was never in any immediate danger, the agent responsible was still removed from Romney's detail and remained in Indianapolis for a debriefing with her superiors.

Secret Service spokesman Ed Donovan told the New York Times the agency was aware of the incident, and the matter "will be dealt with internally and in an appropriate manner."

Romney has been accompanied by Secret Service agents since February.

[photo via AP]