MacBook Air 2011 Grey Screen, no logo, unable to turn off

I recently rebooted my MBA 2011 and got a totally grey screen (no Apple logo) which does not go away.

When I attempt to shut it down by holding the ON/OFF button it appears to turn the screen off only (goes black) but does not shutdown the MBA. Pressing the ON/OFF button brings the totally grey screen back up again.

Any suggestions on how to reboot or shutdown the computer?