Iranian security forces have killed at least 537 people in a crackdown on protests that erupted in September, a rights group said on Tuesday, sharply revising upwards its previous toll.

Norway-based Iran Human Rights (IHR) also said that while four people had been executed in this period on protest-related charges, over 300 more had been hanged on other accusations in the same time frame in what it described as a broad tactic to “intimidate” society.

The protest movement began in mid-September after the death in custody of Mahsa Amini, a young Iranian Kurd who had been arrested for allegedly violating Iran's strict dress code for women.

Protesters took to the streets urging not just an end to clothing obligations like the obligatory headscarf for women, but also the ousting of Iran's Islamic theocracy which has ruled the country since 1979.

The authorities responded with a crackdown that, according to rights groups, saw protesters directly targeted with live ammunition across the country.

IHR's previous toll was of 488 protesters killed in the crackdown, and it said the new figure of 537 was due to new deaths being openly verified.

The most deaths took place in late September with 223 killed, October when 100 lost their lives, and November when 173 died, it said in a report marking 200 days since Amini's death.

The most deaths — 134 — were recorded in Sistan-Baluchistan province in the southeast, where the Baluch Sunni minority has held weekly protests.

At least 69 deaths were recorded in Tehran, and 57 and 56 in the provinces of Kurdistan and West Azerbaijan respectively, which are populated by the Kurdish minority.

Four men were executed in protest-related cases after what IHR described as “show trials” that prompted international outcry.

But the group said in the same period 309 people were also put to death on other charges, including 180 for drug-related offenses, without a murmur of dissent from the international community.

The group said this showed how capital punishment in Iran was used as a “tool to intimidate society.”

“These are the 'low-cost' victims of the regime's execution machine,” IHR director Mahmood Amiry-Moghaddam told AFP.

“Nobody knows them, their executions don't receive any condemnation—but the aim is the same; to spread fear and prevent more protests.” (AFP via VOA)

•PHOTO: FILE - In this photo taken by an individual not employed by the Associated Press and obtained by the AP outside Iran, Iranians protest the death of Mahsa Amini, 22, after she was detained by the country's morality police, in Tehran, Oct. 1, 2022.

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