Ammon News - Iran and Israel targeted each other with missiles and airstrikes early on Saturday after Israel launched its biggest-ever air offensive against its longtime foe in a bid to prevent it from developing a nuclear weapon.

Air raid sirens sounded across Israel, including in Tel Aviv and Jerusalem, sending residents rushing into shelters as successive waves of Iranian missiles streaked across the skies and Israeli interceptors rose up to meet them.

A man and a woman were killed in Israel and dozens wounded by a missile that landed near their homes, Israel's ambulance service said.

Rescue teams were searching the rubble of apartment buildings that were destroyed in Rishon Lezion, a city outside of Tel Aviv.

Israel's Defence Minister Israel Katz said on Saturday the Iranian leadership had crossed a red line by firing at civilians and will "pay a heavy price for it".

In Iran, several explosions were heard overnight in the capital Tehran, the semi-official Tasnim news agency reported.

The Fars news agency said two projectiles hit Tehran's Mehrabad airport, and Iranian media said flames were reported there. Close to key Iranian leadership sites, the airport hosts an air force base with fighter jets and transport aircraft.

Iran's U.N. envoy Amir Saeid Iravani said 78 people, including senior military officials, have been killed in Israel's strikes on Iran and more than 320 wounded, most of them civilians.

Tehran launched waves of airstrikes on Saturday after two salvos on Friday night, Fars reported. One of the waves targeted Tel Aviv, Israel's commercial hub, before dawn on Saturday, with explosions heard as far as Jerusalem, witnesses said.

Those were in response to Israel's attacks on Iran early on Friday against commanders, nuclear scientists, military targets and nuclear sites. Iran denies that its uranium enrichment activities are part of a secret weapons programme.

The U.S. military helped shoot down Iranian missiles headed to Israel on Friday, two U.S. officials said. Israel's military said Iran fired fewer than 100 missiles on Friday and that most were intercepted or fell short. Reuters