Site of the deadly bus crash at Tehran Azad University, Tehran, Iran, December 25, 2018

Iran’s security forces have dispersed protests amid anger over the authorities’ handling of a bus crash that killed nine students and injured 28 last week.

Demonstrators have gathered since Saturday, culminating in security forces confronting the rally on Monday. The marchers have demanded accountability for Iran’s aging buses. They chanted slogans demanding the resignation of Tehran Azad University’s top officials, including the head of the board of trustees, the Supreme Leader’s senior advisor Ali Akbar Velayati.

The deputy governor of Tehran Province, Abdolazim Rezaie, said the protests are illegal as no permit was issued. He asserted that the police had full control of the streets and no arrests had been made.

President Hassan Rouhani has ordered an investigation into the crash.

But others in the regime expressed concern about the demonstration in the context of protests through Iran in the past year, spurred by the country’s economic problems.

The Supreme Leader has warned of “Sedition 2019″, 10 years after mass protests over the disputed Presidential election. Judiciary head Sadeq Larijani said on Monday, “The workers and students have legitimate demands…but they should be vigilant not to advance the enemies’ goals.”

A member of Parliament’s Education Commission said on Monday that the Tehran Azad bus was a salvaged vehicle which had not passed a technical inspection.

Mirhemayat Mirzadeh added that the driver had multiple driving violations and had received warnings over his conduct.