The Israeli military on Thursday warned people to evacuate a city and other communities in southern Lebanon that are north of a UN-declared buffer zone, signalling that it may widen a ground operation launched earlier this week against the Hezbollah militant group.

Israel has told people to leave Nabatieh, a provincial capital, and other communities north of the Litani River, which formed the northern edge of the border zone established by the UN Security Council after the 2006 war in a resolution that both sides accuse the other of violating.

Israel, which has been fighting with Hamas in Gaza for almost a year, sent its troops into southern Lebanon after two weeks of intense air strikes, escalating tensions in a conflict that risks drawing in the United States and Iran.

The evacuation warnings came after Israel bombed central Beirut in an attack the Lebanese health ministry said killed nine people.

Reuters witnesses reported hearing a massive blast, which a security source said had targeted a building in the district of Bachoura a few hundred meters from parliament, the closest an Israeli strike has come to the central downtown district.

"Another sleepless night in Beirut. Counting the blasts shaking the city. No warning sirens. Not knowing what's next. Only that uncertainty lies ahead. Anxiety and fear are omnipresent," UN special coordinator in Lebanon Jeanine Hennis-Plasschaert said on X on Thursday.

A Hezbollah-linked civil defence group said seven of its staff, including two medics, had been killed in the Beirut attack, which Israel said was a "precise" air strike.

Residents reported a sulphur-like smell following the attack, and Lebanon's state-run National News Agency accused Israel of using internationally banned phosphorous bombs.

Human rights groups have in the past accused Israel of using white phosphorus incendiary shells on towns and villages in conflict-hit southern Lebanon.

Israel also said it targeted a municipality building in the southern Lebanese town of Bint Jbeil killing 15 Hezbollah members, while more than a dozen Israeli missiles also hit the southern suburb of Dahiyeh, where Hezbollah leader Hassan Nasrallah was killed last week.

Eight Israeli soldiers were killed in ground combat on Wednesday in south Lebanon as its forces thrust into its northern neighbour.

The Lebanese army said one soldier was killed and another injured in an Israeli strike while carrying out an evacuation and rescue mission with the Lebanese Red Cross in the southern town of Taybeh on Thursday.

"A soldier was killed and another was wounded as a result of an aggression by the Israeli enemy during an evacuation and rescue operation with the Lebanese Red Cross in Taybeh village," the army said.

The Lebanese Red Cross said four of its volunteers were wounded.

The Lebanese army also said a soldier was killed in an Israeli strike on a military post in southern Lebanon, adding that soldiers fired back at the sources of the fire.

As it pushes into south Lebanon, Israel is also weighing its options for retaliation against its arch-foe Iran.

A day after Iran fired more than 180 missiles into Israel, Israel said on Wednesday eight soldiers were killed in ground combat in south Lebanon as its forces thrust into its northern neighbour.

Hezbollah and Israel have traded fire across the Lebanon border almost daily since the day after Hamas's cross-border terror attack on October 7, which killed 1,200 in Israel and took 250 others hostage, according to Israeli figures.

Israel declared war on the militant group in the Gaza Strip in response. More than 41,000 Palestinians have been killed in the territory, and just over half the dead have been women and children, according to local health officials.

Iran said on Wednesday its missile volley — its biggest-ever assault on Israel — was over, barring further provocation, but Israel and the United States promised to hit back hard.

Qatar's Emir Sheikh Tamim bin Hamad Al-Thani called for serious ceasefire efforts to stop Israel's "aggression" in Lebanon and said no peace was possible in the Middle East without the creation of a Palestinian state.

What is happening in the Middle East is a "collective genocide" he said at the Asia Cooperation Dialogue summit in Doha, adding that his country has always warned of Israel's "impunity".

Speaking at the same gathering, Iranian President Masoud Pezeshkian warned against "silence" in the face of Israel's "warmongering".

"Any type of military attack, terrorist act or crossing our red lines will be met with a decisive response by our armed forces."

A total of 1,974 people have been killed in Israeli attacks on Lebanon over the past year, the country's health minister Firass Abiad said on Thursday.

He said those killed include 127 children, and 9,384 others have been injured.

Israel says it killed senior Hamas leader in Gaza three months ago

The IDF said on Thursday that it killed a senior Hamas leader in an air strike in the Gaza Strip around three months ago.

It said that a strike on an underground compound in northern Gaza killed Rawhi Mushtaha and two other Hamas commanders, Sameh Siraj and Sameh Oudeh.

There was no immediate comment from Hamas.

The military said the three commanders had taken refuge in a fortified underground compound in northern Gaza that served as a command and control centre.

It said Mushtaha was a close associate of Yahya Sinwar, the top leader of Hamas who helped mastermind the October 7 attack into Israel.

Sinwar is believed to be alive and in hiding inside Gaza.

Houthis target Tel Aviv

The elimination of Nasrallah dealt a major blow to Hezbollah, which he developed into Lebanon's most influential military and political force with wide reach in the Middle East and removed Iran's most powerful proxy.

Hezbollah, along with Hamas in Gaza, is listed by the Australian government as a terrorist organisation.

Hezbollah and Iran's other regional allies, Yemen's Houthis and armed groups in Iraq, have launched attacks in the region in support of Hamas in its war with Israel.

The Houthis, who have been firing missiles, sending armed drones and launching boats laden with explosives at commercial ships with ties to Israeli, US and UK entities since last year, said they launched a successful attack on Israel's commercial capital Tel Aviv with drones.

Israel said it intercepted a suspicious aerial target in the area of central Israel early on Thursday.

The IDF urged residents of Lebanese villages who have evacuated their homes not to return until further notice.

"IDF raids are continuing," spokesperson Avichay Adraee said on X on Thursday.

More than 1,900 people have been killed and over 9,000 wounded in Lebanon in almost a year of cross-border fighting, with most of the deaths occurring in the past two weeks, according to Lebanese government statistics.

Caretaker Prime Minister Najib Mikati said about 1.2 million Lebanese had been displaced by Israeli attacks.

More than 300 of those displaced have taken shelter in a Beirut nightclub, once known for hosting glitzy parties and where staff are now using their guest-list clipboards to register residents.

"We're trying to keep strong," said Gaelle Irani, who was formally in charge of guest relations, taking a brief break from finding people a corner to live in.

"It's just overwhelming. So overwhelming and sad. But just as this was a place for people to come enjoy themselves, it's now a place to shelter people and we are doing everything we can to help and be there for them."

The Israeli military said regular infantry and armoured units joined ground operations in Lebanon on Wednesday as Iran's missile attack and Israel's promise of retaliation fanned concern of a wider conflict in the oil-producing Middle East.

Israel's addition of infantry and armoured troops from the 36th Division, including the Golani Brigade, the 188th Armoured Brigade and 6th Infantry Brigade, indicated that the operation was expanding beyond limited commando raids.

Western nations including Australia have drafted contingency plans to evacuate citizens from Lebanon after Tuesday's dramatic escalation, but none have launched a large-scale military evacuation yet, though some are chartering aircraft as Beirut airport stays open.

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