Iranian students have vowed to commemorate a violent 1999 attack on a university dormitory tomorrow in defiance of an official ban.
Nervous that the July 9th anniversary may reignite protests against clerical rule which rocked Tehran and other cities for 10 nights in June, officials have banned off-campus rallies, closed some university dormitories and postponed summer exams.
Hundreds of people, including scores of students, are still under arrest after authorities rounded up more than 4,000 people during and after the biggest and most violent pro-democracy protests seen in Iran for four years.
"We haven't obtained any permission for gatherings but there will be some sit-in protests at the universities and some people are going to gather outside the UN building," in Tehran, one student leader said.
Many ordinary Iranians have also pledged to mark the events of July 9th, 1999 when hardline Islamic vigilantes fiercely loyal to Iran's conservative clerics attacked students in a Tehran University dormitory, killing one person and sparking five days of mass protests.