Supreme leader of Iran, Ali Khamenei, was killed following U.S.-Israeli bombardment, Iranian state television confirmed Sunday.

The broadcaster did not provide details about the circumstances of his death.

State media also reported that 40 days of public mourning were declared in Iran.

The Supreme National Security Council said Khamenei was killed at his office early Saturday, and that his death would mark the beginning of a "great uprising against the tyrants of the world.”

Iran’s Revolutionary Guard Corps said it would "decisively avenge” Khamenei’s killing, stressing that "the hand of revenge of the Iranian people will not let go of the killers of the Imam.”