Need help finding a movie

[Matt]

I call upon the vast knowledge of this board to help me identify a mid 80s slasher movie. I don't remember too much about it, except that it was set in the woods and at the very end of the movie the unknown killer turns out to be a man with curly blonde hair who escaped from a insane asylum, and one of the guys he was trying to kill turned out to be his brother. Any ideas?