Iran today fired two security chiefs responsible for a raid on a university dormitory that prompted thousands of students to protest in the strongest expression of discontent since the 1979 Islamic revolution.

The demonstrations, which swelled after police and hard-line activists stormed the Tehran University dormitory Friday, exposed a widening gulf between reformists, who support President Mohammed Khatemi, and conservatives, who control the police and judiciary.

The Iranian government admitted today that one person, an off-duty soldier, had been shot and killed in the raid. About 20 others were hospitalized with serious injuries.

Student leaders, some wearing bandannas to conceal their faces, placed tires and barbed wire today on the main road leading to the dormitory, closing off the street in Tehran. Witnesses said about 10,000 Iranian students demonstrated today in the second day of protests over the assault, demanding the dismissal of those behind the raid.

In a move apparently in line with that demand, Iran's National Security Council said in a statement that Brig. Gen. Sadat Ahmadi and an unidentified deputy had been dismissed and would be handed over to judicial officials, state-run Tehran television said in a broadcast monitored in Dubai.

The council said a third security chief, the commander of the Tehran region, had been reprimanded for failing to "take the appropriate measures." The statement did not give the officers' units.

The off-duty soldier killed in the raid was identified as Ezzatollah Ebrahiminejad, a guest in the dormitory, the television report said, citing the council, which Khatemi heads and which includes senior cabinet ministers and security chiefs.

In his first comments on the raid, Khatemi expressed "deep regret" today, calling the assault an "ugly and bitter incident."

"I will continue investigations until all the aspects of the event are discovered and appropriate action is taken," the president said in a statement carried by the official Islamic Republic News Agency.

Meanwhile, the security council warned students against holding any further demonstrations.

CAPTION: An Iranian student covers her face during the demonstration in Tehran against a Friday raid by police.