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Vast crowds of Iranians loyal to the Islamic Republic have gathered in Tehran for the first day of funeral ceremonies for the country's former supreme leader.

Ayatollah Ali Khamenei was killed in joint US-Israeli airstrikes at the start of the war.

Iranian state media say six days of ceremonies will span several locations across Iran and neighbouring Iraq, before he is buried in his hometown of Mashhad on Thursday.

The BBC's chief international correspondent Lyse Doucet is in Tehran as people prepare to head to the vast complex where the former supreme leader is lying in state.

The BBC's chief international correspondent Lyse Doucet is reporting from Tehran on condition that none of her material is used on the BBC's Persian Service. These restrictions apply to all international media organisations operating in Iran.

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