My ipad wont unlock. It wont even turn off. PLEASE HELP!!!!!

HELP. My ipad wont unlock. I can get on the lock screen. However it seems to be frozen here is what happened. I was on the Internet, then to close the app I pinched it close with all five fingers. However just as the image of the app was about to disappear. The image of the website froze amongst all the other app's. So I locked it thinking that it would unfreeze the ipad. But on the lock screen it has no slide to unlock message. And the thumb sized image of my website is in the middle of the screen. I cant turn it off either.