In the recording, four vehicles—the first flying a blue flag with "TRUMP" and "MAKE AMERICA GREAT AGAIN" emblazoned in white—drive down Interstate 65, according to a report by the Courier-Journal.
IndivisibleKY, a self-described activist organization formed after President Donald Trump's 2016 election victory, posted video of the convoy on its website on Monday.
Chris Rowzee, a spokeswoman for IndivisibleKY, said she was "disturbed" to see the flag on a military vehicle.
"To show a partisan political leaning on a military vehicle is very reminiscent of Nazi Germany," she said, as quoted by the Courier-Journal.
Defense Department spokesman Maj. Jamie Davis said that it would violate regulations to fly that flag on a military vehicle.
"That is not standard procedure,” he said as quoted in the report.
Davis said it would also violate regulations to run a military convoy with no unit markings on the vehicles, and said he did not think the vehicles belonged to any service branch. Per the report, he suggested that they were military surplus.
Tracey Metcalf, administrator for the Military Vehicle Preservation Association, said the color of the convoy suggests the vehicles did or do belong to the Army.
Patrick Hodges, a spokesman for Ft. Knox, told the Courier-Journal that the convoy was not theirs, as did Maj. Stephen Martin, director of public affairs for the Kentucky National Guard.
Army spokeswoman Lt. Col. Jennifer Johnson said that photos of the vehicles were "too blurry to say if they belonged to Army units," according to the report.
Watch the video here.