Iran’s intelligence chief has been killed in an Israeli strike on Tehran on Sunday. Mohammed Kazemi, the head of intelligence for the Islamic Revolutionary Guard Corps, was killed alongside Hassan Mohaqiq, his deputy, and Mohsen Bagheri, a third intelligence officer, during an attack on the capital.

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.

Countries in the region condemned Israel’s attack, while leaders around the globe called for immediate de-escalation from both sides.

Iran's Revolutionary Guards chief Hossein Salami, who was killed in an Israeli air strike on Tehran Friday, was a veteran officer close to Supreme Leader Ayatollah Ali Khamenei known for his tirades against Israel and its US ally.

The attack comes after decades of mutual hostility and a long-running shadow war of covert strikes and sabotage.

Israeli Prime Minister Benjamin Netanyahu's office said on Sunday that at least 13 people have been killed since Friday in Israel by Iranian strikes, as Tehran retaliates to Israel's ongoing attacks on Iranian nuclear facilities, military sites and leaders.

Israel launched blistering attacks on the heart of Iran's nuclear and military structure Friday, deploying warplanes and drones previously smuggled into the country to attack key facilities and kill top generals and scientists -- a barrage it said was necessary before its adversary got any closer to building an atomic weapon.

Israel launched blistering attacks on the heart of Iran’s nuclear and military structure Friday, deploying warplanes and drones previously smuggled into the country to assault key facilities and kill top generals and scientists — a barrage it said was necessary before its adversary got any closer to building an atomic weapon.

Israel launched strikes on Iran’s capital early Friday, with explosions booming across Tehran as Israel said it targeted nuclear and military sites.