Big problem....Help!?

My friend and I told our teacher that our other clmates slipped the answer key to our test earlier.Because of what we said,we were asked to point out those who did it.Then our teacher crumpled their test papers in front of the cl.They were so angry that we heard that they're gonna do something to us.I have no problem If they will do something wrong with me 'coz I studied martial atrs for 2 years.But I heard that they have friends who joined fraternities and I'm worried about my friend.What am I supposed to do with those bitches?