Revealing: When Col. Flagg holds his pistol up to stop Mr. Pak Sr. from leaving, you can see there is no magazine in the pistol.
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Deliberate "mistake": When Flagg turns out the light to escape.
To make that effect they had to freeze a frame and then start again. If you look closely after Flagg turns out the light you can see Hawkeye and the Korean Man on the far right freeze. Then it shows Potter ordering the light back on.