Odds and Ends
Suit up...WITH GUNS
5 3, 7:35am
Uh, that's pretty much every religion ever. Hell, there are still Christian extremist groups like The Lord's Resistance Army that used Child soldiers and regularly executed anyone that didn't convert to christianity, you have the Spanish Inquisition during the Renaissance that would capture Jewish peasants and force them through torture to either confess to crimes they didn't commit (one famous case being the Jewish were constantly blamed for the bubonic plague and poisoning wells) and forcing them to convert, a lot of the time they would still kill the ones that converted and of course Eastern Lightning who slaughter people in China regularly and is behind numerous massacres and terrorist attacks in China.
Then you have Buddhist extremists that have been attacking muslim immigrants, Hindu extremists have been around for ages, Japan saw a lot of Shinto extremist groups during the Mahayana branch of Buddhism's presence and there are even Sikh extremists. Probably every religion has their own terrorist group and extremists either in the past or in the modern age. The only religion probably without extremists is Jainism because their entire philosophy is built around not killing a single thing, even a killing a bug was seen as equal to killing a person.
Hell, you don't even need a religion to be an extremist, we've seen plenty of extremist groups without a religious creed all you need is some form of a philosophy.
By your logic we might as well decree all humans should be blamed for extremism. Not all muslims are extremists or want to chop off someone's head just because they're different just like not all Christians want to kill anyone who is non-white or gay and I can keep on piling up examples.