Tehran said American bases in the Middle East could face reprisals if the U.S. helped repel Iranian attacks on Israel.

Israel launched “preemptive” strikes early Friday across Iran, amid growing regional tensions and concerns about Iran’s nuclear capabilities.

Sirens sounded in Israel as Iran launched dozens of ballistic missiles in retaliation for Israel's strikes on its nuclear facilities.

In response to Israel’s attack, Iran fired back with more than 100 drones. NBC News’ Chief International Correspondent Keir Simmons reports more. Former NATO Supreme Allied Commander retired Gen. Wesley Clark and Senior Fellow at the Carnegie Endowment for International Peace Aaron David Miller join Ana Cabrera to examine the possibility of further attacks.

Israel’s ongoing attacks on Iranian nuclear sites, generals, and scientists killed 78 people and wounded more than 320 on Friday, Iran’s ambassador told the U.N. Security Council, but he said “the overwhelming majority” of victims were civilians. Israel described the new wave of hostilities as the beginning of “Operation Rising Lion.”

Johnson affirmed the U.S. and Israel's shared goal of preventing Iran from acquiring nuclear weapons. Israeli Prime Minister Benjamin Netanyahu stated the operation aims to counter Iran's threat to Israel's existence.