BellaOnline Forums Books and Music Sci Fi/Fantasy Books Help pls- Looking for title of sci-fi/fantasy book

I'm hoping you may be able to help me. I'm trying to remember the title and author of a book I read several years ago. It was a noir-ish urban story based on a regular cop/detective, and through some plot twist that I can't recall (I think he's chasing a serial killer possibly?), he stumbles across the battle of good versus evil (I think the serial killer ends up being a demon). Angels and demons appear as humans on earth to battle- (and I know this is gory but it's one of the few things I remember) they kill by exploding each other's heads. If you can point me in any direction at all, I would greatly appreciate it. I've done countless searches and come up empty-handed, and this book just will not let me go. Any help or direction is appreciated!

Hi, I replied to your email, but I guess either you didn't get it, or it's not Jim Butcher's Fool Moon.

I hope someone knows what it is, because it sounds like something I would like to read

Hi there! I got Fool Moon- it was a cool book, but not the one I had read previously. I think I'm out of luck though- no one else seems to have any ideas, so back to searching! :)