Dhaka, July 4 -- Hundreds of thousands of mourners gathered in Tehran on Saturday as Iran began a dayslong funeral for late Supreme Leader Ayatollah Ali Khamenei, beating their chests in grief before his flag-draped coffin and chanting calls for revenge against Israel and the United States.

Khamenei, who led Iran for decades, was killed at the age of 86 in a Feb. 28 airstrike during the opening phase of the Iran war.

The funeral is expected to strengthen support for Iran's ruling establishment and its new supreme leader, Ayatollah Mojtaba Khamenei, the late leader's son.

The ceremonies come at a critical time as Iran seeks to use its influence over the Strait of Hormuz in negotiations with the United States on a permanent end to the wa...