Administrators at the University of Bremen in northern Germany asked police to break up a pro-Palestinian demonstration on the school’s campus on Wednesday after activists called for more demonstrators to join the action. About 50 people gathered in the university’s Glashalle building without prior permission, the police said. They had also not registered the protest, as required. A police spokeswoman said that efforts to clear the protesters began peacefully on Wednesday. The university said the decision to clear the protesters was made for “security reasons” following calls on social media f…