Where did Itsuwa`s sweater go? (Continuity issue) This question contains potential spoilers for episode 8 of Index 3!

In Episode 8 of Toaru Majutsu no Index III during the battle between the


   Amakusa church members and Aqua of the Rear in the scene where Itsuwa attacks Aqua with the Saint Destroyer we have the following scenes:
 In the first scene Itsuwa is wearing her turtle neck sweater  and she is still wearing it when Aqua strikes her and throws her through the ceiling.  However the moment they show her on the ground the sweater is suddenly gone  During the remaining scenes the sweater remains missing. From the shots it is obvious that Itsuwa did not have the strength nor the means to remove the sweater herself. So now my question is, is this a continuity error in the show or did the sweater disappear in some other way?
It's glossed over in the anime, but in the novels, she was using a spell that diverted damage onto her clothes. When they took that attack, it was enough to burn up the sweater.