Posted videos of the disorder by the gates here:
http://www.northstandchat.com/showthread.php?358862-Palace-fans-ruining-the-night-for-their-own&p=8221508&viewfull=1#post8221508
If those fireworks had effected the play of the game and a goal was scored would it be allowed? Say Palace had a penalty cos Haha dived and one got let off as Ryan went to save it, would the goal stand?