Iranian police have arrested an undisclosed number of protesters who were highlighting the drying up of one of the country’s largest lakes. Lake Urmia, in the mountains of north-west Iran, was once the largest lake in the Middle East but began shrinking in 1995 due to a combination of prolonged drought and the extraction of water for farming and dams, according to the UN Environment Programme. Urmia, one of the largest “hypersaline” — or super salty — lakes in the world, is located between the cities of Tabriz and Urmia, with more than six million people dependent on agriculture around its shores. Between 50 and 70 dams have been constructed on rivers feeding the lake, which used to be a popular spot for tourists, before it shrank to about a tenth of its size. On Sunday, Rahim Jahanbakhsh, the police chief of Iran's West Azerbaijan province, reported the arrests. He described the suspects as “many evil and hostile elements, who had no other objective than to destroy public property and disturb the security of the population,” according to state news agency IRNA. On Saturday, the Fars news agency reported that “dozens of people in the cities of Naghadeh and Urmia had protested against the authorities' lack of attention to the drying up of Lake Urmia”. Fars said protesters had shouted slogans in the provincial capital of Urmia warning the lake was shrinking. “Lake Urmia is dying, parliament orders its killing”, some shouted, Fars reported, with others calling out that “Lake Urmia is thirsty”. Largely arid Iran, like other nearby countries, has suffered chronic dry spells and heatwaves for years, which are expected to worsen with the impacts of climate change. In the last few months, thousands of people have demonstrated against the drying up of rivers, particularly in central and south-western Iran. Lake Urmia is an important ecosystem, a key stopping point for migratory birds, home to an endemic shrimp, and other underwater species.