Her left arm had been ripped off.

A pale blue light like one would see during welding resided deep within the empty red eye socket. The same was true for the left arm. As if to compensate for the missing arm, a dazzling arm of light was jutting out. It must have been made of fairly high energy because it continuously made the sound of a high voltage current frying a bug in a bug zapper.

Toaru Majutsu no Index vol.19 ch.3 pt.13