What you need to know about the violent exchange of fire between Israel and Lebanese Hezbollah

By Joseph Krauss, Associated Press

Israel and Lebanon's Hezbollah launched their fiercest exchange of fire on Sunday after months of strikes and counterattacks that raised fears of all-out war.

By mid-morning, the exchange of fire appeared to have ended, with both sides claiming to have targeted only military targets. Israeli strikes killed three militants in Lebanon, while no casualties were reported on the Israeli side. But the situation remains tense.

Here is an overview of the current situation:

What happened early Sunday?

Israel said about 100 warplanes launched airstrikes targeting thousands of rocket launchers in southern Lebanon to thwart an imminent Hezbollah attack. Hezbollah later said it launched hundreds of rockets and drones targeting military bases and missile defense positions in northern Israel and the Israeli-annexed Golan Heights.

Hezbollah called the attack an initial response to the targeted killing of one of its founding members and senior commanders, Fouad Shukur, in an Israeli airstrike in Beirut last month. It said its military operations on Sunday were over and would allow it to strike deeper into Israel in the future. It denied Israel’s claims that it had foiled the attack, without providing evidence to support its own claims.

Two Hezbollah fighters and a militant from an allied group were killed and two people were wounded in the strikes on Lebanon. Israeli military spokesman Lt. Col. Nadav Shoshani said an initial assessment indicated “very little damage” in Israel.

How likely is an all-out war between Israel and Hezbollah?

Sunday's firefight did not trigger the much-feared war. The firepower of both sides and the absence of civilian casualties could allow both sides to claim some sort of victory and back down. But tensions remain high.

Hezbollah began firing rockets and drones at Israel shortly after the outbreak of the Gaza war, sparked by Hamas' surprise attack on Israel on October 7. Hezbollah and Hamas are allies, both backed by Iran. Israel has responded with airstrikes, and the near-daily exchanges have intensified in recent months.

More than 500 people have been killed in Lebanon by Israeli strikes since October 8, mostly fighters from Hezbollah and other armed groups, but also more than 100 civilians and non-combatants. In northern Israel, 23 soldiers and 26 civilians have been killed by strikes from Lebanon. Tens of thousands of people have been displaced on both sides of the border.

Israel has promised to restore calm to the border to allow its citizens to return home. It has said it prefers to resolve the issue diplomatically, through the United States and other mediators, but will use force if necessary. Hezbollah officials have said the group is not seeking a wider war but is prepared for one.

What would a war between Israel and Hezbollah look like?

In 2006, Israel and Hezbollah fought a month-long war that left much of southern Beirut and southern Lebanon in ruins and drove hundreds of thousands of people from their homes on both sides.

Everyone expects the next war to be much worse.

Hezbollah has about 150,000 rockets and is capable of striking all regions of Israel. It has also developed an increasingly sophisticated drone fleet and is experimenting with precision-guided missiles. A full-scale war could force hundreds of thousands of Israelis to flee, cripple the Israeli economy and force the army, still engaged in Gaza, to fight on two fronts.

Israel has promised a crushing response to any major Hezbollah attack that would devastate Lebanon's civilian infrastructure and economy, which has been mired in crisis for years. The southern suburbs of Beirut and towns and villages in southern Lebanon, where Hezbollah's main strongholds are located, would likely be razed.

An Israeli ground invasion to eradicate Hezbollah could take years. The militant group is far more advanced and better armed than Hamas in Gaza, which is still holding out after 10 months of intense Israeli bombardment and ground maneuvers.

Would a war involve the United States, Iran and other countries?

An all-out war between Israel and Hezbollah could escalate into a regional conflict.

Iran is a backer of Hezbollah, Hamas and other militant groups in Syria, Iraq and Yemen. Iran has vowed to carry out its own retaliation after Hamas leader Ismail Haniyeh was killed in an explosion in its capital last month that was widely blamed on Israel. Israel has not said whether it was involved.

Iranian-backed groups across the region have repeatedly attacked Israeli, American and international targets since the start of the Gaza war and may intensify their attacks in an attempt to relieve Hezbollah.

The United States, for its part, has provided unwavering support to Israel and has deployed a vast array of military assets in the Middle East in recent weeks to try to deter any retaliatory strikes by Iran or Hezbollah. The USS Abraham Lincoln recently joined another carrier group in the region.

In April, a U.S.-led coalition helped shoot down hundreds of missiles and drones fired by Iran toward Israel in response to an Israeli strike in Syria that killed two Iranian generals. Both sides downplayed a possible Israeli counterattack on Iran, and tensions have gradually eased.

What does this mean for ceasefire efforts in Gaza?

The United States, Egypt and Qatar have been trying for months to broker a ceasefire in Gaza and the release of dozens of hostages held by Hamas. Those efforts have become more urgent in recent weeks, with diplomats calling such a deal the best hope for easing regional tensions.

Hezbollah has said it would stop its attacks along the border if a ceasefire is reached in Gaza. It is not yet clear whether Hezbollah or Iran would stop or reduce their threats of retaliation following the deaths of Shukur and Haniyeh, but neither wants to be seen as an obstacle to a possible ceasefire.

Despite the intensity of diplomatic efforts, significant differences remain, including Israel's demand for a lasting presence along two strategic corridors in Gaza, a demand rejected by Hamas and Egypt. High-level talks will be held in Egypt on Sunday.