In Tel Aviv, daily life now revolves around the sound of air raid sirens.

When the alarms blare, people on the streets quickly funnel into the nearest shelter. In many apartment buildings, residents open secured basement doors so strangers outside can rush in.

Sirens have sounded as often as every hour following the U.S-Israel attack on Iran that killed its Supreme Leader and other influential figures. Many shops have closed, and streets that are normally busy have thinned out as ballistic missiles launched from Iran streak toward Israeli cities.

Some of the missiles have penetrated Israel’s air defense systems. Nine people were killed Sunday in Iranian strikes, authorities said.

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Retaliation has extended beyond Israel. U.S. military installations across the Middle East have also come under attack. About 40,000 American troops are stationed in the region.

Video circulating online appeared to show a missile striking in Bahrain, home to the Navy’s Fifth Fleet. U.S. officials have said personnel were able to take shelter before impact and that no casualties were immediately reported there.

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The broader conflict has already claimed American lives. U.S. Central Command confirmed that four U.S. service members have been killed since the fighting began. Defense Secretary Pete Hegseth said the deaths occurred during Iran’s initial retaliatory response to U.S. and Israeli strikes.

Adding to the complexity of the conflict, three U.S. fighter jets were accidentally shot down in what officials described as friendly fire from Kuwaiti air defenses. All six airmen ejected safely and survived. U.S. officials said there is no indication of ill will from Kuwait, a key regional partner that allows American forces to operate from its bases.