EA relays the details:
[A] reported group of 200 around the home of Hojetoleslam Ghavami, where Karroubi was staying for a mourning ceremony, attacked the residence with stones and bricks. City officials and even the provincial governor tried to stop the assault but were unsuccessful. After four hours and the advice of “special forces” (possibly his State-appointed security detail) and anti-riot police, Karoubi decided to leave Qazvin for Tehran.
As the car was leaving the complex, shots were fired at it, breaking the supposedly bullet-proof windows. Karroubi said that there was not much his protection team could do; firing back in defence would have led to their prosecution. He added that only God knows why the guns that are supposed to be used only to defend the nation and the country are used against the people.
The Dish 