Alec Baldwin -- Threatens NYC Reporter ... 'You're As Dumb as You Look'

Another fun Alec Baldwin moment ... this time, the "30 Rock" star THREATENED a local news reporter ... and then called him ugly to boot.

Baldwin was walking back to his Manhattan apartment moments ago when he was approached by a reporter from FOX5 in NYC.

As the reporter tried to ask a question about the stalker case, Baldwin said, "If you're still here when my wife and kid come out, you're going to have a big problem, you know that don't ya?"

Alec turns to walk inside his building and throws out one last barb -- "You ARE as dumb as you look. You are with Fox, right?"