There is no direct answer to such problems, as individual cases differ from each other, and extremism incites to violence and violent reactions. Education depends too much on the budgets and funds granted by authorities, parties, religious, "economic" or secular interests, the surroundings, mentalities, and local or federal politics and trends. Scandals can harm or even destroy renowned institutions, their lead and their teachers, which might incite the decision makers of these institutions to "walk on egg shells" ...
Also in education, it is a struggle between the small and the great ones, and if, in certain cases, students might better focus on discretion, learning and "staying out of trouble", but there is, unfortunately, no real safety, as even exemplary students may be attacked - quite randomly - and prevention ought to start from the very first "symptoms" with open discussions and/or therapeutic "confrontations" and/or role plays between the conflicting parties under the close supervision of neutral experts and teachers, before disputes get out of control. Sadly enough, that is rarely the case, all the more, if politics and religions or doctrines are involved ...
Furthermore, certain associations, fraternities, clubs, etc. might have certain influences.
And the police is often called too late and gets, of course, the blame, if their officers intervene vigorously against extremist rioters, whatever their side.
And violent groups should not be admitted to the university.