Police are using tear gas to disperse farmers who have been on a two-week-long peaceful sit-in to protest water shortages in the region.
Iranian security forces have used tear gas, batons and apparently birdshot during clashes with protesters demonstrating in Isfahan in support of farmers angry over water shortages.
Social media posts showed officers in the central Iranian city apparently opening fire with birdshot on Friday in the dried up riverbed of the Zayandeh Rud, the largest river in the drought-stricken region, and nearby streets.
The semi-official news agency Fars said demonstrators threw rocks and set fire to a police motorcycle and an ambulance.
State TV showed police firing teargas at demonstrators gathered in the dried riverbed. A video posted on social media showed protesters chanting back: "Shame on you!"
Another news agency, ISNA, said farmers and authorities struck an agreement Thursday on the distribution of 50 million cubic metres (over 1.6 billion cubic feet) of water.
Despite the deal, it said hundreds of people gathered in the riverbed following a call on social media by "suspect and counter-revolutionary elements", and clashes ensued.
Social media videos showed several injured protesters, at least one with apparent birdshot pellet wounds.
Farms run dry, prompting protests
Overnight, farmers holding a two-week-long peaceful sit-in to protest against water shortages in the region were dispersed by unidentified men who set fire to their tents. Social media posts said they were security forces while state media said they were "thugs".
State media earlier said farmers had agreed to leave after reaching a deal with authorities.
The farmers in Isfahan province have for years protested against the diversion of water from the Zayandeh Rud to supply other areas, leaving their farms dry and threatening their livelihoods.
A pipeline carrying water to Yazd province has been repeatedly damaged, according to Iranian media.
In July, protests broke out over water shortages in the oil-producing southwest, with the UN human rights chief criticising the fatal shooting of protesters. Tehran rejected the criticism.
Iran has blamed its worst drought in 50 years for the water shortages, while critics also point to mismanagement.