Warning: The following story contains graphic details of violence that some readers might find upsetting.

A BBC News Persian analysis of hundreds of videos and photographs taken during recent protests in Iran confirms the security forces' use of a wide range of weaponry, including machine guns, sniper rifles, and shotguns.

Protesters were reportedly killed in many of the more than 200 cities where protests had been recorded. While the exact death toll remains unclear, the level of brutality and the deployment of lethal weaponry evidenced in pictures, witness accounts, and reports by human rights groups and the media show thousands have been killed across the country.

The crackdown on protests—which began over the economy but rapidly escalated—employed a level of violence unprecedented in modern Iranian history. This is the largest mass killing in contemporary Iranian history and one of the largest in the world, Payam Akhavan, an Iranian Canadian former UN prosecutor at the International Criminal Court, in The Hague, told BBC News Persian.

The Iranian government has blamed the killings on rioters and terrorists. But BBC News Persian analysis shows security forces used a number of different weapons on protesters, including machine guns, sniper rifles, assault rifles, shotguns, handguns, pellet-firing paintball guns, tear gas, machetes, knives, batons, large wooden clubs, and green laser sights and pointers (for blinding and targeting).

Footage from cities such as Tehran, Isfahan, Yazdanshahr, and Shahsavar, verified by BBC News Persian, shows both heavy—such as the DShK—and medium—such as the PK—machine guns mounted on military pickup trucks. These were reportedly used for crowd control and to impose a state of siege.

Witnesses confirm that sniper rifles were widely used during the January protests, with verified footage showing two figures in black tactical uniforms of the type worn by several branches of the security forces, including the IRGC, on a hotel rooftop, with a Dragunov sniper rifle leaning against a wall.

In another shocking example, plainclothes agents have been seen wielding machetes and attacking protesters. BBC News Persian's investigation confirmed the widespread use of shotguns, resulting in numerous permanent injuries, including many eye traumas due to metal pellets.

As the world watches, the brutality of the Iranian regime’s responses raises urgent calls for accountability and justice for the lives lost and forever changed in these violent confrontations.