It seems to me that a group with "ultra" in their description is in itself an "extremist" group. Ultra means extreme, does is not? Any group that throws stones at cars going to hospitals on Shabbat is obviously an EXTREMIST group. Little grace towards others, so why do they think they deserve grace themselves?
Preliminary report: Palestinian stabs man near Damascus Gate, Jerusalem (Haaretz)
from the article: Ultra-Orthodox Jews ask Israeli media to help rid them of extremists