Lebanon's health ministry said four people were killed Tuesday in Israeli strikes in the country's south, while Hezbollah said its militants launched barrages of rockets and drones at Israeli forces.
Israeli forces have traded near daily cross-border fire with Iran-backed Hezbollah, an ally of Palestinian group Hamas, since the war on Gaza began in October.
But fears of a major escalation have grown in recent weeks after the Israeli killing of a top Hezbollah commander.
On Tuesday, Lebanon's health ministry said "Israeli enemy strikes on the village of Dhayra" killed four people and wounded two others, after earlier reporting three dead.
It did not say whether the casualties were civilians or fighters.
Hezbollah claimed a string of attacks on Israeli troops and positions, including sending barrages of Katyusha rockets at several north Israel military positions in stated retaliation for Israeli strikes, including in Dhayra.
The group also said it launched "squadrons of explosive laden drones" and "intense rocket barrages" at several Israeli positions in the annexed Golan Heights in response to Israeli strikes deep in east Lebanon's Bekaa Valley a day earlier.
The Israeli military in separate statements said a total of around 115 "projectiles" were identified crossing from Lebanon.
It also said that "numerous suspicious aerial targets were identified crossing from Lebanon", with air defences intercepting some of them.
No injuries were reported, though the military said the incidents sparked fires in some areas.
The military also said air forces struck projectile launchers and several "Hezbollah military" structures in south Lebanon.
Lebanon's health ministry said three emergency personnel from the Hezbollah-affiliated Islamic Health Committee were hurt when the Israeli military "targeted them" in south Lebanon, causing "significant damage to the ambulance they were travelling in".
The ministry "condemned in the strongest terms the repeated targeting of health workers in south Lebanon".
Several militant groups in Lebanon operate health centres and emergency response operations, with at least 21 rescue workers killed since October, according to an AFP tally.
The violence has largely been restricted to the Lebanon-Israel border area, but fears of a major escalation have mounted since Hezbollah and Iran vowed to respond to twin killings blamed on Israel late last month.
An Israeli strike on Beirut's southern suburbs killed a top Hezbollah commander, Fuad Shukr, shortly before an attack in Tehran blamed on Israel killed Hamas political leader Ismail Haniyeh.
The cross-border violence has killed some 589 people in Lebanon, mostly Hezbollah fighters but also including at least 128 civilians, according to AFP's tally.