A 22 year old woman was arrested by morality police in Tehran on the 13th of September for allegedly violating Iran's strict rules requiring women to cover their hair. The protests have swelled with demands from more freedoms to an overthrow of the state. So if you do something defiantly, it means you do it in a way that strongly shows that you will not obey. A crackdown is when police or government use a lot of force to punish people who are breaking the law.