Iranian authorities say they expect up to 35 million people to take part in the funeral ceremonies for late Supreme Leader Ali Khamenei , as police declared a state of high alert ahead of a nationwide series of events spanning three cities.
The 86-year-old Iranian leader, who came to power in 1989, was killed in airstrike on 28 February, at the beginning of the US-Israeli war on Iran.
The announcement comes as authorities prepare for what could become the largest funeral gathering in modern history, with extensive security and traffic measures planned to accommodate the expected crowds.
According to Iran's Tasnim news agency, farewell ceremonies will be held on 3 and 4 July at Tehran's Mosalla prayer grounds, followed by a funeral procession in the holy city of Qom on 5 July.
Khamenei's body will then be transferred to Iraq on 7 July before returning to Iran for final funeral rites and burial in his hometown of Mashhad on 8 July.
The head of Iran's Traffic Police said officials estimate that between 30 and 35 percent of Iran's population will participate in the ceremonies.
Authorities expect between six and 17 million mourners in Tehran, between three and five million in Qom, and between 3.5 and eight million in Mashhad, bringing the nationwide total to around 35 million people.
Police said they had held a series of meetings with traffic and road authorities to develop a comprehensive plan, including road closures and traffic restrictions tailored to the locations and timings of the ceremonies to facilitate the movement of mourners and maintain security.
The deputy head of Iran's Traffic Police operations said around 1.9 million vehicles are expected to enter Tehran during the ceremonies, with around 30 percent arriving via roads from Alborz province and the Karaj Expressway, 16 percent via the Pardis Expressway and 13 percent via the Tehran-Qom highway.
Authorities also expect around 450,000 vehicles to enter Qom and between 1.3 million and 1.4 million vehicles to travel towards Mashhad.
The traffic plan includes restrictions on heavy vehicles, mobile fuel stations, dedicated lanes for emergency services and the deployment of medical centres around ceremony sites to ensure the smooth movement of crowds and speedy response to emergencies.
Khamenei was killed alongside several senior military commanders, government officials and members of his family during a joint US-Israeli strike on Tehran.
His death triggered only the second succession of the Islamic Republic's supreme leadership since the 1979 Revolution, with the Assembly of Experts later appointing his son, Mojtaba Khamenei, as his successor.
While the Iranian government's estimates seem very high, an estimated 10.2 million mourners - around one-sixth of the population at the time - attended the funeral of Iran's first supreme leader, Ayatollah Ruhollah Khomeini, in 1989.
If official attendance estimates are realised, the ceremonies would far exceed those held for Ayatollah Khomeini, which is the largest known funeral gathering and one of the largest gatherings in human history.
The event descended into chaos as mourners overwhelmed security, forcing officials to briefly delay the burial after crowds surged around Khomeini's coffin. At least eight people were killed and hundreds injured in the crush.