What happened on Iran's 'Bloody Saturday'?

In a place called Malekshahi, in western Iran, protesters converge on a base run by the revolutionary guards.

They bang on the gates and throw stones at the walls and give voice to their collective rage. In Iran, the economy is imploding, and people are struggling to survive.

The revolutionary guards respond with gunfire. Some protesters flee, others collapse on the spot, as bystanders attempt to carry the casualties away.

They will go on to call what happened 'Bloody Saturday'. The following day, 4 January, the protest reforms outside the main entrance of the regional hospital.

Relatives of people who had been shot and injured in multiple gatherings, call for the end of the regime. The security forces move in, on foot and on motorcycles, and gather in front of the facility.

Staff and civilians try to stop them from entering but the authorities force their way through the front door. Amnesty International says security personnel entered the hospital on multiple occasions, arresting injured protesters and members of their family.

The human rights group says they also took bodies away to prevent displays of mourning. In images posted online, a patient hides inside his room as the security forces tear through the wards.

The demonstrations, which began on 28 December, are reported to have reached over 280 locations in 27 of Iran's 31 provinces. The Sky News Data and Forensics team has independently geolocated and verified video of protests in 19 provinces.

The demonstrations follow a collapse in the value of the Iranian currency, the rial, and a period of prolonged hyperinflation. At the time of Iran's 2015 nuclear deal with world powers, $1 traded for 32,000 rials.

On Tuesday, $1 was trading at 1.46 million rials - a new low - with no signs of slowing. The economy has been badly damaged by US sanctions, along with mismanagement and corruption.

Conditions further deteriorated after last year's war with Israel. The rebellion began in Tehran, when shopkeepers - or bazaaris - took to the streets.

As the currency deteriorates, they can neither stock nor sell their goods. Huge protests at the city's Grand Bazaar, the beating heart of public life in Iran, are seen as a power symbol of this anger.

With an annual inflation rate running at approximately 40%, the price of basic staples - like cooking oil, meat, rice and cheese - is increasing beyond the means of the vast majority. Yet the government lacks the resources to alleviate the situation.

Yassamine Mather, an Iranian scholar and political expert, told Sky News: "The government didn't try to hide that there were such protests, partly because I think they've learned from previous (protests) that people will read on social media and see videos and look at foreign TV stations. Read more:Everything you need to know about Iran protests "On the one hand, they are saying they are legitimate protests, and they try to negotiate or talk to people.

"And on the other hand, they're coming down very hard on (the protesters) who are getting attacked by the police and therefore retaliate. So the cycle of violence is inevitable." Around 500 miles south of the capital in Shiraz, southwestern Iran, a protester sprays the security forces with fuel, then lights the stream - his fire extinguisher turned into a flamethrower.

An officer is seen covered in flames. After initially running away, the protester is caught and beaten in full public view, despite a pledge by US President Donald Trump on Friday to 'rescue the protesters' if the authorities use extreme force.

Back in Malekshahi, funerals take place for the dead. A survivor of 'Bloody Saturday' anonymously told Sky News: "The assault on the hospital and the way the Islamic Republic attacked the people of Malekshahi can be described based on established humanitarian principles, as crimes against humanity." Additional reporting by Sophia Massam, digital investigations journalist.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories.

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