The war in the Middle East triggered by the joint US and Israeli attack on Iran expanded dramatically on Monday, with casualties and destruction reported across at least nine countries, including major strikes on Tehran.

Since the US and Israel first struck Iran with bombing and missile attacks over the weekend, the speed at which this war has exploded into a regional conflict is ‘dizzying’, says the Guardian’s Oliver Holmes. Tehran swiftly retaliated to the attacks, which killed the country’s supreme leader, by launching strikes across the Middle East.

• A visual guide to the US-Israeli war on Iran and Tehran’s response

• US-Israel war on Iran – live updates