Israel has launched blistering attacks on the heart of Iran’s nuclear and military structure, deploying warplanes and drones previously smuggled into the country to assault key facilities and kill top

The U.S. says it wasn't involved in the strikes on Iran, but three American officials told NBC News the U.S. is assisting in shooting down Iranian missiles and projectiles targeting Israel.

Aerial attacks between Israel and Iran continued overnight into Monday, marking a fourth day of strikes following Israel's Friday attack. That surprise strike hit the heart of Iran's nuclear program,