(TMZ) Katt Williams wasn't done after leading cops on a crazy three-wheeled chase through Sacramento on Sunday -- because moments later, he was in a Target department story ... where he hit an employee in the face ... and TMZ has footage of the face-to-hand contact.
There's no audio, so we can't tell what the argument is about -- but by the looks of the employee's body language before the wallop (placing his hand on his chest) the guy wasn't looking for a fight.
Then out of nowhere Katt winds up and slaps him in the face -- at which point the employee pulls out his phone and, according to an eye witness, he calls police.
Video of the aftermath surfaced on the Internet this week, showing Katt making his getaway in an electric cart ... before police arrive. Watch the video here.