Fars news agency uploaded a film showing a little bit of hostage situation at University of Tehran see it here: Clip of this situation at University of Tehran
According to Fars news agency the hostage taker, a former Sergeant first class of Iran’s police force, entered the salon, fired one shot and asked students to close the doors.
He let those who were afraid to leave and then distributed some CDs about law enforcement activities and some documents about his employment at police force. He let students to take films with their mobile phones and then started to give a talk about his experience as a police officer to 200 students present. He surrendered himself without resistance afterwards.
The clip does not make much sense, but the students certainly were clapping for him!
Link to University of Tehran: http://www.ut.ac.ir/en/index.htm