Persian-language broadcaster Iran International reported that at least 12,000 people were killed during a nationwide crackdown in Iran, describing it as the deadliest episode of state violence in the country’s modern history.

According to the report, the killings occurred mainly over two consecutive nights amid widespread protests. Iran International said its findings are based on cross-checked information from multiple sources, including individuals close to Iran’s security institutions, medical staff, eyewitnesses, families of victims, and data from hospitals in several cities.

The outlet stated that the crackdown was organized and coordinated, not the result of isolated clashes, and that most victims were allegedly killed by Iran’s security forces, including units linked to the Islamic Revolutionary Guard Corps and the Basij. Many of the dead were reportedly under the age of 30.

The report also highlights a near-total media blackout, including large-scale internet shutdowns and the suspension of most domestic newspapers, which it says has made independent verification difficult and delayed public reporting.

Iran International added that it will continue to document the events, collect evidence from the public, and share verified findings with relevant international bodies. Iranian authorities have not publicly confirmed the figures.