Three U.S. service members have been killed and another five have been seriously wounded, in the first casualties of the unfolding U.S. operations against Iran, the U.S. military said on Sunday.

Hundreds of protesters have stormed the US Consulate in Karachi, Pakistan, smashing windows hours after Ayatollah Ali Khamenei was killed in a joint US-Israeli attack.

Iran said it had launched a large-scale attack on 27 US military bases and Israeli defence installations, according to state media.

The conflict between the US and Iran is a “fight to the death”, the former US national security council spokesman said

The strait ⁠is the world’s most vital oil export route, which connects ⁠the biggest Gulf oil producers, such as Saudi Arabia, Iran, Iraq ​and the United ‌Arab Emirates, with the Gulf of Oman and the Arabian ‌Sea.

“A short while ago, the IDF identified missiles launched from Iran toward Israel”, it said in a statement.

The US and Israel launched a daylight attack on Iran on Saturday morning.

Trump’s claim that Iran will soon have a missile that can hit the US is not backed by U.S. intelligence reports, and appears to be exaggerated, casting doubt on part of his case for a possible attack on the Islamic Republic.

The United States and Iran made progress in talks over Tehran's nuclear program on Thursday, mediator Oman said, but hours of negotiation ended with no sign of a breakthrough that could avert potential U.S. strikes amid a massive military buildup.

Iran and the U.S. hold the latest round of talks in Geneva on Thursday aimed at resolving their longstanding nuclear dispute and averting new U.S. strikes on Iran following a large-scale military buildup.