AFPTV images from Beirut's southern suburbs showed mangled buildings and burned-out vehicles after heavy Israeli bombing overnight, with tens of thousands fleeing the destruction.

The war, now entering its seventh day, has dragged in global powers, upended the world's energy and transport sectors, and brought chaos to even usually peaceful areas of the volatile region.

Powerful explosions shattered the skies above Iran's capital Tehran early Friday as Israel said it was striking "regime infrastructure" in the city.

Internet coverage is running at about one percent, according to monitor group Netblocks, limiting information about the impact of the war on ordinary Iranians.

In Tehran, the war has emptied the usually traffic-jammed streets but residents told AFP that security forces are keeping a tight grip on the population.

The powerful Islamic Revolutionary Guard Corps (IRGC) "has closed almost every main street with armed personnel and heavy machine guns to frighten people", a 30-year-old Tehran resident told AFP from Paris.

"The people are the real enemy in their eyes, not the Americans. Their extremists say first you have to deal with the enemy at home."

Friday morning's strikes on Tehran followed warnings from Israel and the US they were stepping up their attacks, first launched on Saturday in a barrage that killed Iran's supreme leader Ayatollah Ali Khamenei.

"We are now moving to the next phase of the operation," Israel's military chief Lieutenant General Eyal Zamir said in a televised statement.

"We have additional surprises ahead which I do not intend to disclose," he added.

US Defence Secretary Pete Hegseth also announced "firepower over Iran and over Tehran is about to surge dramatically".

President Donald Trump said it would be a "waste of time" currently to send ground troops into Iran, but has insisted he would "have to be involved" in choosing Iran's next leader.

According to Iran's health ministry, US and Israeli strikes on the country have killed 926 people, a number AFP could not independently verify.

Iran has launched missile and drone attacks at Israel and the Gulf since the war began. In Israel, at least 10 people have been killed, according to first responders there.

The US military has reported the deaths of six of its personnel since the war began Saturday.

- 'We were humiliated' -

The conflict has drawn in Israel's neighbour Lebanon after militant group Hezbollah launched missiles in support of its backer Iran.

Israel struck several towns in the south of the country overnight, with widespread destruction in the southern Beirut suburbs, considered a Hezbollah stronghold and home to an estimated 600,000 to 800,000 people.

AFP correspondents on the ground saw scenes of panic and terror as residents fled en masse after an unprecedented Israeli order to evacuate immediately if they wanted to save their lives.

Hundreds of families milled around on Beirut's Ramlet al-Baida beach, left with nowhere to go.

"We fled from the suburbs, we were humiliated," one man told AFP, declining to give his name.

"We'll sleep on the road tonight and God alone knows what will happen to us."

Israel's military chief Zamir has ordered troops to expand the area under his army's control in southern Lebanon, whose health ministry said 123 had been killed in strikes.

Iran has kept up its attacks on Israel, with a volley of missiles aimed at Tel Aviv while rocket trails also lit up the sky in Netanya, further north.

- 'Volatility remains elevated' -

The war has not spared the rich countries of the Gulf, formerly seen as a tourist hot spot and rare Middle East safe haven.

Qatar intercepted a drone attack on a US air base on its territory early Friday, while Saudi Arabia shot down three drones east of its capital Riyadh.

Thirteen people, seven of them civilians, have been killed in Gulf countries since the war began, including an 11-year-old girl in Kuwait.

The conflict has expanded as far afield as the Sri Lankan coast, where a US submarine torpedoed an Iranian frigate, and Azerbaijan, which threatened retaliation after a drone hit an airport.

Nations have scrambled to repatriate holidaymakers caught up in the fighting with air traffic severely limited as missiles and drones dominate the skies above the region.

The Gulf region's reputation as a paradise for influencers and luxury tourism has taken a battering as Iranian missiles have struck hotels and residential buildings.

The war has also hammered global markets and sent crude oil prices soaring by about a fifth in the week since fighting erupted, all but drying up shipping in the critical Strait of Hormuz.

"Unless the war ends soon -- and if anything a more intense conflict seems more likely -- markets will struggle," said IG chief market analyst Chris Beauchamp.

"Volatility remains elevated... but a continued decline for the moment seems likely."

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