Hours after the US and Israel said an air strike had killed Ayatollah Ali Khamenei as part of the most ambitious series of attacks on Iran in decades, Iranian state media confirmed the 86-year-old leader's death on Saturday.
US President Donald Trump said the air strikes were aimed at ending a decades-long threat from Iran and ensuring it could not develop a nuclear weapon as he sought to justify a risky gambit that seemed to go against his professed opposition to American involvement in complex overseas conflicts.
"This is not only Justice for the people of Iran, but for all Great Americans, and those people from many Countries throughout the World, that have been killed or mutilated by Khamenei and his gang of bloodthirsty THUGS," Trump wrote on Truth Social after Khamenei's body was found.
Experts said while the deaths of Khamenei and other Iranian leaders would deal the country a major blow, it would not necessarily spell the end of Iran's entrenched clerical rule or the Revolutionary Guards' sway over the population.
Israel's military said its strikes on Sunday morning targeted Iran's ballistic missile and air defence systems.
Iran's armed forces would soon retaliate again with their biggest offensive against US bases and Israel, Islamic Revolutionary Guard Corps vowed in a statement on Sunday.
Air raid sirens repeatedly sounded across Israel on Sunday morning, warning residents of an incoming attack.
In Tel Aviv, a series of explosions were heard as Israel's sophisticated air defence system sought to intercept the latest Iranian offensive.
There was no immediate report of any damage or injuries.
Witnesses in the Gulf cities of Dubai and Doha heard several loud blasts.
Iran had responded to Saturday's initial attacks by launching hundreds of missiles and drones targeting US troops and cities in Israel and Arab countries allied with Washington, prompting widespread cancellations of Middle East flights.
A senior US intelligence official told Reuters while the largest threat stemming from the attack was against US military personnel in the Middle East, cyber attacks could also target critical US infrastructure.
Major Middle Eastern airports, including Dubai, the world's busiest international travel hub, were shut on Saturday after the strikes on Iran's missile retaliation unleashed one of global aviation's most severe disruptions in years.
Dubai's landmark Burj Al Arab hotel and the airport, which handles more than 1000 flights a day, were damaged in an overnight attack on sites across the Arab Gulf states that also hit airports in Abu Dhabi and Kuwait.
Tehran warned the Strait of Hormuz, the narrow passage through which one-fifth of global oil consumption passes, had been closed, raising expectations of a sharp jump in oil prices.
Iran's ambassador to the UN, Amir Saeid Iravani, told an emergency meeting of the UN Security Council on Saturday hundreds of civilians had been killed and injured in the US and Israeli strikes.
Iravani called Iran's retaliatory attacks a matter of self-defence, saying the bases of hostile forces were legitimate military targets.
UN Secretary-General Antonio Guterres, who called for an immediate cessation of hostilities, told the council he deeply regretted an opportunity for diplomacy had been "squandered".
Earlier, he condemned the strikes and the retaliation by Iran, saying they undermined international peace and security.
China called for an immediate ceasefire, urging all sides to avoid escalation and resume talks, while the official Xinhua news agency criticised the attacks on Sunday as "brazen aggression against a sovereign nation".
Witnesses said some Iranians took to the streets in Tehran, the nearby city of Karaj and the central city of Isfahan to celebrate after reports of Khamenei's death emerged.
Videos posted on social media, which Reuters was unable to immediately verify, also showed celebrations in other locations.
Israel and the US timed the attacks to coincide with a meeting of Khamenei and his top aides.
Khamenei was working in his office when the attack occurred, Iranian state media said. His daughter, grandchild, daughter-in-law and son-in-law were also killed.
The Revolutionary Guards issued a statement mourning the loss of "a great leader".
Trump, in a social media post, called him "one of the most evil people in history".
Trump and Israeli Prime Minister Benjamin Netanyahu called on Iranians to rise up and overthrow their government in the wake of the attacks, which Israel's military said had taken out at least seven senior military commanders.
