Across Iran’s capital, Tehran, explosions rang out overnight as the U.S. and Israel pounded Iran with airstrikes. Iran and its allies have hit back against Israel, neighboring Gulf states and targets critical to the world’s oil and natural gas production.

The conflict has also spread to Lebanon, where the Iranian-supported militant group Hezbollah fired missiles at Israel on Monday, prompting Israel to retaliate.

On Tuesday, the Israeli military hit Beirut with more airstrikes and said it had moved additional troops into southern Lebanon and taken new positions on several strategic points close to the border. The U.N. peacekeeping force in Lebanon later said its peacekeepers saw Israeli troops going into and then out of Lebanon. But Israel’s army said its troops are still operating in Lebanon.