This was the first fragging I've heard of in almost 30 years
Fragging did happen quite a few times in Vietnam but, as far as I can determine, hasn't happened since. So, if that's accurate, then you could say that 100% of all fragging incidents in the past 30 years were caused by Muslims.
And of course, that would be pointless. This was a very isolated incident by a single individual. I've heard conflicting news reports that he was either a lifelong Muslim or a recent convert. Sometimes, recent converts are more zealous, giving rise to sayings like "more Catholic than the Pope."