Israel likely used US-made 2,000-pound bombs to kill Hezbollah leader, analysts say

Days after massive Israeli air strikes killed Hezbollah's leader Hassan Nasrallah, new information has emerged to piece together how it unfolded.

Footage from the scene shows the blasts levelled multiple high-rise apartment towers in the densely populated suburb known as Dahiyeh.

Other buildings sank into the ground, surrounded by pancaked concrete and twisted metal spanning an area larger than a soccer field.

Although the Pentagon has not confirmed, a US senator who chairs a defence committee has said an American-made 2,000-pound (900-kg) bomb was used in the strikes.

And several analysts say it's likely the US "bunker busters" were involved in the biggest attack to hit Beirut since the start of the current conflict in the Middle East, almost a year ago.

More than 80 bombs dropped

Israel Defense Forces (IDF) said they were aware of Nasrallah's whereabouts for months and conducted the air strike to exploit a brief window of opportunity.

Two IDF officials told the New York Times that more than 80 bombs were dropped over a period of several minutes to kill the 64-year-old leader of the Iran-backed militant group.

They did not confirm the weight or make of the bombs.

The Israeli military told residents in parts of Beirut's southern suburbs to evacuate late on Friday.

That night, it carried out what the IDF called a "precise strike" on Hezbollah's headquarters, which it said were "embedded under residential buildings in the heart of the Dahiyeh in Beirut".

At least six people were killed, and 91 others injured, according to the Lebanese Health Ministry.

Among those killed were the commander of Hezbollah’s southern front, Ali Karaki, and the Islamic Revolutionary Guards Corp's commander in Lebanon.

AP reported some people at the scene on Sunday were still searching for missing relatives.

US-made bombs appear in IDF video

The IDF released videos and photos following attacks it said showed the warplanes that took part in the strike.

Analysts who examined the footage for the Washington Post said it appeared the fighter jets were carrying multiple 2,000-pound-class bombs, some of which were US-made BLU-109s.

They added that they were equipped with Joint Direct Attack Munition (JDAM) guidance kits, which convert "dumb bombs" into precision-guided munitions that can attack a specific target.

Michael Shoebridge, director and founder of Strategic Analysis Australia, agreed with the analysis.

"The pictures released by the IDF show F-15s equipped with those heavy bombs," he told the ABC.

US officials said they did not know Israel was going to launch an air strike aimed at killing Nasrallah.

But President Joe Biden praised the move as "a measure of justice for his many victims".

Hezbollah has been designated as a terrorist group by the US and Australia.

US halted heavy bomb supply

The US is Israel's longtime ally and biggest arms supplier.

In May, the Biden administration announced it had paused a shipment of US-made 2,000-pound bombs to Israel because of concerns over civilian safety in Gaza.

Mr Biden acknowledged that the bombs, which military experts say turn "earth into liquid", had killed civilians.

Over the weekend, Senator Mark Kelly, chair of the Senate Armed Services Airland Subcommittee, said Israel had used a US 2,000-pound Mark 84 series bomb in the strikes that killed Nasrallah.

"We see more use of guided munitions, JDAMs, and we continue to provide those weapons," Mr Kelly said in an interview with NBC.

"That 2,000-pound bomb that was used, that's a Mark 84 series bomb, to take out Nasrallah."

Neither the Israeli military nor the Pentagon have commented on the weapons used in the attack.

Although the US announced that it had halted shipments of heavy bombs to Israel, Mr Shoebridge said Israel would likely have a stockpile.

Bombs designed to explode underground

The Mark 84, or BLU-117, is the largest in the Mark 80 series of weapons known as "bunker busters".

It has a lethal fragmentation that can extend for up to 365 metres.

Malcolm Davies, senior analyst in defence capability at the Australian Strategic Policy Institute (ASPI), said there were different variations of the heavy bombs.

But he was confident Friday's strikes in the Dahiyeh neighbourhood used bunker busters.

"The high-yield, 2,000-pound weapons were designed to penetrate deep underground where Nasrallah was hiding with his cronies," he told the ABC.

"So I think that that's how the Israelis did this."

The bombs slice through concrete, then explode underground.

The explosions then create shock waves that immediately collapse structures above.

Largest Israeli strike

Trevor Ball, a former explosive ordnance disposal technician for the US Army, told the Washington Post that videos of the aftermath showed it was possible dozens of 2,000-pound bombs were used.

Mr Shoebridge said in kinetic terms, the strikes that killed Nasrallah were the largest single strike by Israel over the past year.

And although the US had voiced concerns about heavy bombs being used in Gaza, the US would likely argue that the strikes were "a clearly targeted strike which had the intended effect".

"Despite its the devastation, this was a precisely targeted attack that killed the most senior leader of this long-term terrorist organisation, plus a bunch of his associated most senior leaders," Mr Shoebridge said.

"I would suspect that the US government position would be that this was a proportional use of force."

Israel and Hezbollah are locked in their most intense round of fighting in decades, teetering on the brink of all-out war.

They have been trading fire across the border since the start of the war in Gaza, which was triggered by the October 7 attack on Israel by Hamas militants.

Hamas militants killed about 1,200 people during the October 7 terrorist attacks on Israel, and took at least 250 hostages back to Gaza, according to Israeli authorities.

Israel responded by invading the Gaza Strip in an ongoing conflict that has claimed the lives of more than 40,000 Palestinians, according to the Gaza health ministry.

Over the past two weeks, Israel has ramped up its attacks on Hezbollah, carrying out strikes across Lebanon that have killed more than 1,000 people and injured thousands more, according to official government updates from Beirut.

Israel says it aims to make its northern areas of the country safe for 60,000 residents to return to their homes after a year of Hezbollah bombings.

'Israel's not going to stop'

With the US presidential elections looming, experts say it is unlikely the Biden administration will take any further action against Israel.

Hussein Ibish, senior resident fellow at the Arab Gulf States in Washington, said restricting weapons sales to Israel could only go so far.

Israel already rejected global calls for a 21-day ceasefire, instead vowing to "continue fighting with full force".

And even after Nasrallah's death, Prime Minister Benjamin Netanyahu said Israel's attacks across Lebanon would not be slowing down.

"The United States and its allies were pushing very hard for a ceasefire and Israel decided 'no, they are just going to go ahead with major escalations anyway because it served their interests'," Professor Ibish told ABC's RN Breakfast.

"The United States is not going to punish Israel five weeks before an election."

Dr Davis said even though Israel had already taken out several of Hezbollah's senior and mid-level leadership, it appeared they were determined to "finish the job".

"They've cut the head off the snake … but Israel's not going to stop," he said.

"So if there's no ceasefire, and no peace settlements, it's just going to keep going."