The Israeli military, meanwhile, said it intercepted a "hostile aircraft" and two projectiles that crossed into Israeli territory from Lebanon.

Israeli officials have warned the military will strike Beirut's southern suburbs, a Hezbollah stronghold, if the group targets northern Israeli communities, a stance they say has backing from Washington.

Hezbollah said its fighters on Wednesday attacked Israeli troops who have invaded southern Lebanon, but the group has not claimed a cross-border attack since Monday.

Israeli and Lebanese diplomats are to hold a second day of direct talks in Washington -- the fourth round since the fighting erupted on March 2, when Hezbollah entered the Middle East war on the side of its backer Iran with rocket fire at Israel.

Hezbollah is sharply opposed to the direct negotiations.

Lebanon's state-run National News Agency (NNA) said an Israeli strike targeted "a car on the Khaldeh road".

An AFP correspondent saw an ambulance and onlookers gathering at the strike site, located on the main highway heading south from the capital.

The NNA reported strikes on more than 20 locations in the south, some after Israel's military warned residents of several villages to evacuate.

The health ministry said an Israeli attack on Al-Hawsh near the city of Tyre killed four Syrians and two Palestinians.

But an Israeli military spokesperson told AFP's Jerusalem bureau that "we are not aware of any such attack having occurred in the area".

- Paramedics -

The health ministry said an Israeli strike elsewhere in the south targeted an ambulance, killing two paramedics from the Risala Scouts Association, which is affiliated with Hezbollah ally the Amal movement.

The ministry circulated images of a badly damaged ambulance, with medical masks spilling out of the vehicle and scattered on the road.

At least 130 emergency and health workers have been killed since the fighting began.

Lebanon's army said a soldier was also killed in an Israeli strike, while an officer and a soldier were wounded in a separate attack on a military vehicle.

The force decried Israel's "deliberate targeting of army personnel, vehicles and positions".

On Tuesday, Israel's military alleged that Hezbollah members were operating in Tyre's Christian quarter -- an area so far spared Israeli evacuation warnings and strikes targeting the rest of the city -- and warned it would order people to leave should the group remain there.

An AFP correspondent said the situation in Tyre was relatively calm on Wednesday morning, adding that some people who had been sleeping in cars or tents at the edge of the Christian quarter left for other parts of the city.

The mayor toured the area late on Tuesday alongside a Lebanese army intelligence officer and a member of the Christian clergy, seeking to reassure residents.

- Petition -

A petition calling for Tyre to be declared an "open city" free of any armed presence and urging Lebanon's military to deploy there has garnered more than 180 signatures, including local lawyers and intellectuals.

Hezbollah has a strong presence in Tyre, and some signatories have since been attacked on social media for their stance.

More than 200 people have signed a similar petition concerning Nabatieh, another large south Lebanon city that has come under Israeli attack.

Israel has recently escalated its attacks and is staging its deepest ground offensive into Lebanon in two decades.

On Monday, US President Donald Trump said he had brokered a deal that Lebanon said would at first halt Israeli attacks on Beirut and Hezbollah attacks on Israeli territory, before expanding in scope.

Senior Hezbollah official Mahmud Qomati told AFP on Tuesday that the group "will not accept a partial ceasefire".

Tehran has insisted that any deal to end the wider Middle East war include Lebanon, saying this week that Israel's expanding campaign there threatened a weeks-long US-Iran ceasefire in the Gulf.