Beirut/Jerusalem: An Israeli airstrike on Beirut killed a senior Hezbollah commander on Tuesday as cross-border rocket attacks by both sides increased fears of a full-fledged war in the Middle East.

Israel's military said the airstrike on the Lebanese capital killed Ibrahim Qubaisi, who it said was the commander of Hezbollah's missiles and rocket force.

Two security sources in Lebanon described him as a leading figure in the Iran-backed group's rocket division. The attack dealt another blow to Hezbollah after a series of setbacks at the hands of Israel over the past week, and Israel later said it was carrying out "extensive strikes" on Hezbollah targets.

The pressure on Hezbollah has increased fears that nearly a year of conflict will explode and destabilise the oil-producing Middle East, where a war between Hamas and Israel is already raging in Gaza.

Israel is shifting its focus from Gaza to the northern frontier, where Hezbollah has been firing rockets into Israel in support of Hamas, which is also backed by Iran. Prime Minister Benjamin Netanyahu said Israel would continue to pound Hezbollah targets and urged Lebanese citizens to escape the grip of Hezbollah leader Hassan Nasrallah.

"Anyone who has a missile in their living room and a rocket in their garage will not have a home," Netanyahu said at an army base at an undisclosed location after the military said it had found ammunition in people's homes.

"Our war is not with you, our war is with Hezbollah. Nasrallah is leading you to the brink of the abyss...Rid yourself from Nasrallah's grip, for your own good." Israel has accused Hezbollah of hiding its weapons in homes and villages in Lebanon, allegations the Lebanese group denies.

'A Very Difficult War'
Israel struck the Hezbollah-controlled area of Beirut for a second consecutive day after mounting a new wave of airstrikes on targets in Lebanon. Hezbollah said it had fired rockets into northern Israel earlier on Tuesday. The Lebanese health ministry said at least six people were killed and 15 wounded in Tuesday's strike on a building in the Ghobeiry neighbourhood of Beirut.

The Israeli government has made securing the northern border and returning residents there a war priority, setting the stage for a long conflict, while Hezbollah has vowed that it will not back down until a ceasefire is reached in Gaza.

Lebanese authorities said 558 people had been killed in airstrikes on Monday, including 50 children and 94 women. A further 1,835 were wounded, they said, and tens of thousands more have fled for safety.

"We felt as if we were in a war, a very difficult war," said Rima Ali Chahine, 50, speaking at a makeshift shelter for displaced people at a Beirut college. "Maybe it didn't take us long on the road, but families are now arriving who have been stuck on the roads since yesterday - 15 or 16 hours on the roads."

The casualty tolls and the intensity of the attacks by the most powerful and advanced military in the Middle East have spread panic in Lebanon, but also defiance among people who recall the devastating Israel-Hezbollah war in 2006. "We are waiting for victory, God willing, because as long as we have a neighbour like Israel, we can’t sleep safely," said Beirut resident Hassan Omar.

Calls for Diplomacy
Calls for diplomacy are growing as the conflict worsens, with UN human rights chief Volker Turk urging all states and actors with influence to avert further escalation in Lebanon.

White House national security adviser Jake Sullivan told MSNBC that he believed "a path forward" could still be found to de-escalation and a diplomatic solution. Urging restraint, British Prime Minister Keir Starmer called for "all parties to step back from the brink."

The fighting has raised fears that the United States, Israel's close ally, and regional power Iran, which has proxies across the Middle East - Hezbollah, Yemen's Houthis and armed groups in Iraq - will be sucked into a wider war. Hezbollah last week suffered heavy losses when thousands of pagers and walkie-talkies used by its members exploded in the worst security breach in its history.

The operation was widely attributed to Israel, which has a long history of sophisticated attacks on foreign soil. It has not confirmed or denied responsibility. Israel's intelligence and technological prowess has given it a strong edge in both Lebanon and Gaza. It has tracked down and assassinated top Hezbollah commanders and Hamas leaders.

But Hezbollah has proved resilient during decades of hostilities with Israel. The group, founded by Iran's Revolutionary Guards in 1982 to counter an Israeli invasion of Lebanon, is considered a more formidable enemy than Hamas. Hezbollah used a new rocket, Fadi 3, in an attack on an Israeli army base, the group announced in a message posted on Telegram on Tuesday.

Its media office Israel was dropping leaflets with a "very dangerous" barcode on them onto Lebanon's eastern Bekaa Valley, warning that scanning it by phone would "withdraw all information" from any device.

There was no immediate comment from the Israeli military. Pan-Arab television station Al-Mayadeen said a journalist working with the station's website, Hadi al-Sayyed, had been killed in an Israeli strike on his hometown on Monday.

It brings the toll of journalists killed in Lebanon since October to four, including two other Al-Mayadeen journalists killed last November and Reuters visuals journalist Issam Abdallah, who was killed by Israeli tank fire last October.