Yes, that's a hand in the crocodile's jaws. It actually belongs to his veterinarian. It's doctor, Chang Po-yu, was going to remove tranquilizer darts through the cage before treating the 200-kilogram reptile when it suddenly had the urge to snap and bite the hand off. Fortunately for Chang, shots were fired at the annoyed croc and it dropped the hand. Don't worry, the crocodile wasn't hit. Later, doctors reattached Chang's hand. Too bad for the crocodile, "there'd be no Chang Po him for lunch from now on!"
For a video of another veterinarian's arm getting bitten off by another crocodile, go to i-Mash.