No idea about the period or anything, but could it have been they got arrested not because they were prominent leaders of the revolution but because they were Jewish and it was a good occasion as any to round them up?
It would make sense they'd be scapegoated, no?
Anti-Semitism was a policy of Nicholas and Alexander III. It certainly led to a lot of resentment in the Jewish community and when the violence broke out, it's logical that Jews would be more likely to participate.
Possible that the Jews were singled out as a group? Maybe but:
The violence is most intense in areas of large Jewish populations
The authorities generally realized that anti-Semitic violence had to be contained not out of love of the Jews but because after they beat up the Jews, they might turn on us
Non-official sources point to the prominence of Jews in many of the revolutionary movements
The original point wasn't the Revolution was a Jewish revolt but that a lot of Jews were driven to opposition to the regime and therefore participated in the violence. As long as Nicholas pursued such policies and he stubbornly pursued them to the end of the regime, these resentments would remain. By analogy, suppose an outbreak of violence happened in America in the 1930's over the depression. Would it stun us to find out that large segments of the black community took part to press the issue of Jim Crow?