Help! Is this the film where...

Okay, saw a film about Vampires years and years ago (though obviously not that long ago if its this film) but basically, all I can remember is a group of guys chasing and hunting down vampires. Can't remember how, but midway through the film we're at some party and if my memory serves me, the lead vampire knocks on the door... it's answered and theres a full on gore shot of the vampire sticking his hand through the drunk guys stomach, then slicing him from the stomach upwards with his hand - when his hand reaches the top of this guys body theres an awesome shot of this guys body just splitting in half.
Okay, sorry if the description wasn't accurate but what film am I thinking about? I'm pretty sure John Carpenter's name was somewhere in the title so any help would be appreciated, thanks.