TEHRAN, Iran -- With hundreds of protesters jailed for demanding the ouster of the ruling Islamic establishment, Iranian student leaders vowed Tuesday to defy a government ban on street rallies and mark the fourth anniversary of a bloody raid on a university dormitory.

"We are being beaten up, intimidated and jailed. We are exhausted. Yet, we will hold rallies to cry for freedom and democracy and demand justice for those who raided our dormitory and still remain free," a reformist student leader said. He asked not to be identified, fearing arrest.

Iran on Monday banned street protests to mark the anniversary of July 9, 1999, raid by police and hard-liners on the Tehran University dormitory. One person was killed and injured at least 20 others.

Those attacks triggered six days of nationwide protests, the worst since the 1979 Islamic revolution that toppled pro-U.S. Shah Mohammad Reza Pahlavi.

None of those who stormed the dormitory in 1999 were punished.

The anniversary is seen as a key date for the future of the elected government of President Mohammad Khatami.

While protesters regularly condemn unelected hard-line clerics and support Khatami, student-led protests two weeks ago for the first time called for the ouster of the ruling establishment and denounced Khatami for failing to fulfill promises.

"To avoid July 9 turning into a national movement for change, the authorities continue to arrest influential students and intimidate every person who has joined protests so far," said another student leader.

The pair, both students at Khajeh Nasir University in Tehran, were summoned to court Tuesday and were told to return Wednesday for further questioning.

"First of all, interrogators said we were accused of provoking riots and asked us to explain why we protested. And then we were asked what we would do if the U.S. attacked Iran," said the first leader.

The two students, leaders of the Office for Fostering Unity, Iran's largest reformist student group, said members were paying a heavy price for democratic reforms, being betrayed by Khatami and jailed by hard-liners.

"Khatami was elected on the promise of democratic changes. But he has done nothing to promote legitimate freedoms or democracy. He has only delayed the collapse of the establishment," the second leader said.

In a move to limit protests, the government closed universities in Tehran last week and allowed students to go home without final exams. Many of students studying at universities in Tehran come from provincial cities.

"We've been told to attend end of semester exams in September. They don't want us to go to university because they are afraid of student protests," said student Hadi Amouzegar.

Amouzegar said he didn't expect a big change on July 9 because the authorities are "in full security control" and "succeeded intimidating students."

But the two student leaders said they were prepared to pay the price for street protests.

"We need to provoke our disappointed nation to demand its rights," the first leader said.

The protests two weeks ago, the largest in months, began with students demonstrating against plans to privatize universities and snowballed into broader displays of opposition to Iran's clerical establishment, led by supreme leader Ayatollah Ali Khamenei.

The protests largely stopped after a large security deployment and the unleashing of hardliners to attack the protesters.