BB Bold :: 9700 Keypad Does Not Work?

My bold 9700 stopped working for no reason! The keypad stoped working all of a sudden. I cannot type in my pin, the trackpad doesn't function, the unclock button on top doesn't work and after a few seconds the screen goes black and the only way to bring the light back on is to either connect it to my laptop via USB which will show the clock and once the USB is removed I get the home screen but cannot do anything there again; or i have to remove the battery and reboot but again I would get the black acreen and the cycle would continue.

My email, text messages, missed calls, facebook notifications and all come thru alright and the red light flashes to indicate this and I get the little sign on top of home screen but cannot access anything as the keypad and the trackpad are both completely non-responsive.

I called my mobile from a landline but again i cannot accept the call as pressing the green call button or any other key for that matter doesn't work. I could access the device via the BB desktop software and have backedup and updated the firmware (i was using the most uptodate version untile now without any problems) . The phone has not gotten wet and hasn't been in any damp environment. I haven't got any dodgy apps or security issues for instance as aresult of opening sapm etc.