Iran says its missile attack on Israel is over – barring further provocation – while Israel and the US have promised to retaliate against Tehran as fears of a wider war intensify.

Despite calls for a ceasefire from the United Nations, the United States and the European Union, fighting between Israel and Hezbollah has continued

Israel renewed its bombardment of Beirut's southern suburbs, a stronghold of the Iran-backed armed Hezbollah group, with at least a dozen airstrikes against what it said were targets belonging the group.

Large plumes of smoke were seen rising from parts of the suburbs. Israel issued new evacuation orders for the area, which has largely emptied after days of heavy strikes.

Hezbollah said it confronted Israeli forces infiltrating the Lebanese town of Adaisseh early on Wednesday and forced them to retreat.

Rockets from Iran fill the sky over Jerusalem and people run for shelter. - Reuters

Iran described its most recent assault on Israel as defensive and solely aimed at its military facilities. Iran's state news agency said three Israeli military bases had been targeted.

Washington said it would work with longtime ally Israel to make sure Iran faced "severe consequences" for Tuesday's attack, which Israel said involved more than 180 ballistic missiles.

The United Nations Security Council scheduled a meeting about the Middle East for Wednesday, and the European Union called for an immediate ceasefire.

"Our action is concluded unless the Israeli regime decides to invite further retaliation. In that scenario, our response will be stronger and more powerful," Iranian Foreign Minister Abbas Araqchi said.

Israel renewed its bombardment early on Wednesday of Beirut's southern suburbs, a stronghold of the Iran-backed armed Hezbollah group, with at least a dozen airstrikes against what it said were targets belonging the group.

Large plumes of smoke were seen rising from parts of the suburbs. Israel issued new evacuation orders for the area, which have largely emptied after days of heavy strikes.

Iran missile fragments on ground in occupied West Bank. – AP

Iran's attack marked it biggest ever military blow against Israel.

Sirens sounded across the country and explosions rattled Jerusalem and the Jordan River valley as the entire population was told to move into bomb shelters.

No injuries were reported in Israel, but one man was killed in the occupied West Bank, authorities there said.

Israeli Prime Minister Benjamin Netanyahu promised arch foe Iran will pay for the missile attack.

“Tonight, Iran again attacked Israel with hundreds of missiles," Netbanyahu said. "This attack failed. It was thwarted thanks to Israel's air defence system, which is the most advanced in the world.

"I congratulate the IDF for its impressive achievement. I also thank the United States for its support in our defence effort.”

Netanyahu says Iran's missile attack on Israel failed, warns Tehran 'will pay'. – AP

As Washington expressed full backing for its longtime ally Israel, Iran's armed forces said direct intervention by Israel's supporters against Tehran would provoke a "strong attack" from Iran on their "bases and interests" in the region.

Oil prices shot up 5 per cent on fears of a wider war between the two arch enemies, and the UN Security Council scheduled a meeting on the Middle East for Wednesday.

"Iran made a big mistake tonight – and it will pay for it," Netanyahu said.

"The regime in Iran does not understand our determination to defend ourselves and our determination to retaliate against our enemies.”

Iran's Revolutionary Guard Corps said the assault was in retaliation for Israeli killings of militant leaders and aggression in Lebanon against the Iran-backed armed movement Hezbollah and in Gaza.

Fears that Iran and the US would be drawn into a regional war have risen with Israel's intensifying assault on Lebanon in the past two weeks, including the start of a ground operation there on Monday, and its year-old conflict in the Gaza Strip.

People take cover on the side of the road in Israel amid Iran's missile strike. – AP

In its attack on Tuesday, Iran fired more than 200 ballistic missiles at Israel, Israel said. Alarms sounded across Israel and explosions could be heard in Jerusalem and the Jordan River valley. Israelis piled into bomb shelters and reporters on state television lay flat on the ground during live broadcasts.

Iran's forces used hypersonic Fattah missiles for the first time, and 90 per cent of its missiles successfully hit their targets in Israel, the Revolutionary Guards said.

Israeli air defences were activated and most missiles were intercepted "by Israel and a defensive coalition led by the United States", Israeli Rear Admiral Daniel Hagari said, adding:

"Iran's attack is a severe and dangerous escalation."

Central Israel received "a small number" of hits and there were other strikes in southern Israel, he said. The Israeli military published video of a school in the central city of Gadera that was heavily damaged by an Iranian missile.

No injuries were reported in Israel, but one man was killed in the occupied West Bank, authorities there said.

US Navy warships fired about a dozen interceptors against Iranian missiles headed toward Israel, the Pentagon said.

Israeli air defenses fire on Iranian missiles targeting Tel Aviv. – AP

US President Joe Biden expressed full American support for Israel and described Iran's attack as "ineffective". He said there was an active discussion about how Israel would respond, and he would confer with Netanyahu.

Vice President Kamala Harris, the Democratic candidate for US president, backed Biden's stance and said the USwould not hesitate to defend its interests against Iran.

Israel vowed consequences for the onslaught.

"We will act. Iran will soon feel the consequences of their actions. The response will be painful," Israel's UN Ambassador Danny Danon told reporters.

The White House similarly promised "severe consequences" for Iran and spokesman Jake Sullivan told a Washington briefing the USwould "work with Israel to make that the case".

Sullivan did not specify what those consequences might be, but he stopped short of urging restraint by Israel as the US did in April when Iran carried out a drone and missile attack on Israel. The Pentagon said Tuesday's airstrikes were about twice the size of April's assault.

Dozens of projectiles seen in skies above Jordan. – AP

Any Israeli response to Tuesday's missile attack would be met with "vast destruction" of Israeli infrastructure, Iran's General Staff of the Armed Forces said in a statement carried by state media, also promising to target regional assets of any Israeli ally that got involved.

Iran's foreign ministry said its operation was defensive and only directed at Israeli military and security facilities. Earlier, Iran's state news agency said Tehran targeted three Israeli military bases. 

UNSecretary-General Antonio Guterres condemned what he called "escalation after escalation", saying: "This must stop. We absolutely need a ceasefire."

EU foreign policy chief Josep Borrell also called for an immediate regional ceasefire. "The dangerous cycle of attacks and retaliation risks ... spiralling out of control," he posted online.

US condemns Iran's attack as significant escalation. – Reuters

A senior Iranian official said the order to launch missiles at Israel had been made by the country's Supreme Leader Ayatollah Ali Khamenei.

Khamenei remains in a secure location, the senior official added.

The previous round of Iranian missiles fired at Israel in April – the first ever – were shot down with the help of the US military and other allies. Israel responded at the time with airstrikes in Iran, but wider escalation was averted.

The Pentagon said the scope of Tuesday's airstrikes was about twice the size of April's assault.

Escalation in Lebanon 

Iran had vowed to retaliate following Israeli strikes that killed the top leadership of its ally Hezbollah in Lebanon, including the group's leader Hassan Nasrallah, a towering figure in Iran's network of fighters across the region.

Hamas, the Iran-backed militant group in Gaza, praised the Iranian missile strikes, saying they avenged Israeli assassinations of three militant leaders, including Nasrallah.

Palestinians in the Gaza Strip, locked in nearly a year of war, celebrated as they watched dozens of rockets en route to Israel. Some of those rockets fell in the Palestinian enclave after being intercepted by Israel but caused no deaths, witnesses said.

Israel said overnight that its troops had launched ground raids into Lebanon, though it described the forays as limited.

In Beirut, Israeli strikes killed the commander of the Imam Hussein division, Israel's military said, referring to a Hezbollah-linked group based in Syria.

Gazans celebrate as skies over Israel flooded with missiles. – AP

Nearly 1900 people have been killed and more than 9000 wounded in Lebanon in nearly a year of cross-border fighting, most in the past two weeks, according to Lebanese government statistics on Tuesday.

But a ground campaign into Lebanon for the first time in 18 years pitting Israeli soldiers against Hezbollah, Iran's best-armed proxy force in the Middle East, would be a major regional escalation.