"Trying to make political points, and that's not how a commander in chief operates. You don't turn national security into a political issue, certainly not right when it's happening," he said during an angry exchange.
Romney hit back strongly, accusing Obama of going on a fundraising tour the day after the September 11 assault on the Benghazi consulate and declaring that his Middle East policy was "unravelling before our very eyes."
But Obama retorted: "The suggestion that anybody on my team, whether it's a secretary of state, our UN ambassador, anybody on my team, would play politics or mislead when we've lost four of our own, governor, is offensive.
"That's not what we do. That's not what I do as president, not what I do as commander in chief," the president declared, fixing Romney with an angry stare then turning on his heel and heading back to his seat.