According to online video analysis, protesters angered by a building that collapsed in southwestern Iran and killed at least 32 people shouted out an emissary from Supreme Leader Ayatollah Ali Khamenei. This triggered a crackdown which saw riot police fire tear gas and club demonstrators.
The protest directly challenged the Iranian government’s response to the disaster that struck a week ago. This is amid rising pressure in the Islamic Republic due to rising food prices and other economic problems caused by the collapse of the nuclear agreement with the world powers.
Although the protests appear to be unleaderless so far, Arab tribes from the region joined them Sunday, increasing the risk of the unrest getting worse. Already tensions between Tehran, Iran and the West have risen after Iran's Paramilitary Revolutionary Guard seized two Greek oil tanks seized at sea.
Ayatollah Mohsen Heidari AleKasir attempted to reach out to the grieving mourners at the site of the Metropol Building's 10-story height, but hundreds turned out Sunday night and booed and screamed instead.
In his 60s, the ayatollah was surrounded by bodyguards and tried to continue, but couldn't.
"What's going on?" The cleric stage-whispered his thoughts to a bodyguard who then leant in to give him some information.
The cleric addressed the crowd once more: "My dears dears, please remain calm. As a mark of respect for Abadan, its martyrs, and the dear (victims), the entire Iranian nation is in mourning tonight."
The crowd responded by shouting "Shameless!"
The live broadcast of the event was then cut from state television. Later, demonstrators chanted "I will Kill; I Will Kill the One Who Killed My Brother!"
Hamshahri, a Tehran-based newspaper, and the semi-official Fars news agency reported that protesters attacked the station where state TV had installed its camera. They cut off the broadcast.
The police ordered the crowd to stop chanting slogans against Islam Republic, and then they ordered them to move on. This made their rally illegal. Later video showed officers confronting protestors and kicking them as they hurled tear gas at them. One officer shot what appeared to have been a shotgun. However, it wasn't immediately clear if this was live fire or "beanbag" rounds that were intended to stun.
It was not immediately clear if any person was hurt or if there were any arrests made by police.
These videos corresponded with known features of Abadan which is located approximately 660 km (410 miles) southwest Tehran. Farsi-language foreign television channels reported that tear gas and other shots were fired.
Iran is extremely difficult for independent newsgathering. Iran has restricted the movement of journalists within the country and disrupted telephone communications and internet access during unrest. Reporters Without Borders identifies the Islamic Republic as the third worst country for journalists, after Eritrea and North Korea.
Authorities have confirmed that the Metropol Building's owner and corrupt officials allowed the construction to continue despite concerns about its poor workmanship. As part of an extensive investigation into the disaster, 13 people were arrested by authorities. This includes the mayor.