Israel launched a wave of strikes on Iran early Friday ahead of a planned UN Security Council meeting to discuss attacks on Iranian civilian infrastructure, while Iran and the United States appeared at a diplomatic impasse.
Smoke also rose over Beirut, although Israel did not immediately report hitting the Lebanese capital, while air raid sirens sounded in Israel as the military said it was working to intercept Iranian missiles.
The US has been pushing Iran to start talks on a 15-point proposal for a ceasefire, but at the same time has ordered thousands more troops to the region, possibly in preparation for a military attempt to wrest the Strait of Hormuz from Iran's tight grip.
More than 1,900 people have been killed in Iran since the war began, according to the Health Ministry, while at least 13 American troops have been killed.