The man in the crosshairs is Keith Appling -- who played at Michigan State from '10 to '14.
Officials say ... security outside of the Pantheion strip club in Michigan witnessed Appling pulling a firearm out of the trunk of his car in the parking lot and called cops.
When police arrived, officials say Appling was in the driver's seat -- and they decided to search the car.
Cops say the found a handgun under the seat and a loaded gun in the trunk. According to multiple reports, the gun in the trunk was an AK-47 assault rifle.