Israel warned residents of south Lebanon "not to return" to their homes on Saturday as Hezbollah said it launched missiles across the border on Yom Kippur, the holiest day in the Jewish calendar.
In cities around Israel, markets were closed and public transport halted as observant Jews fasted and prayed.
But with the country at war, troops remained engaged in combat in Hamas-run Gaza and in southern Lebanon, a traditional Hezbollah stronghold, amid a firestorm of criticism over the wounding of four UN peacekeepers.
In a message addressed to south Lebanese, Israeli military spokesman Avichay Adraee wrote on X: "For your own protection, do not return to your homes until further notice... Do not go south; anyone who goes south may put his life at risk."
The war between Israel and Hezbollah has since September 23 killed more than 1,200 people in Lebanon, according to an AFP tally of Lebanese health ministry figures, and forced more than a million to flee their homes.
On Saturday, Hezbollah said it had launched missiles at an Israeli army base near the northern city of Haifa.
In a statement, the group said its fighters were "targeting the explosives factory there with a salvo of... missiles".
Air raid sirens sounded in northern Israel, with the Israeli military saying it had intercepted a projectile launched from Lebanon.
Israel began pounding Gaza shortly after suffering its worst ever attacks from Iran-backed Hamas militants on October 7 last year, and it launched a ground offensive against Hezbollah in Lebanon on September 30.
After the Yom Kippur holiday, attention is likely to turn again to Israel's expected retaliation against Iran, which launched around 200 missiles at Israel on October 1.
'Deliberately targeted'
On Friday, Israel faced severe diplomatic backlash over what it said was a "hit" on a United Nations peacekeeping position in Lebanon.
Two Sri Lankan peacekeepers were hurt in the second such incident in two days, the UNIFIL mission said Friday.
The Israeli military said its soldiers had responded with fire to "an immediate threat" around 50 metres (yards) from the UNIFIL base in Naqura.
But the Irish military's chief of staff, Sean Clancy, said it was "not an accidental act" while French President Emmanuel Macron said he believed the UN peacekeepers had been "deliberately targeted".
Both Ireland and France are major contributors to UNIFIL.
As Israel faced a chorus of condemnation by UN chief Antonio Guterres, Western allies and others, its military pledged to carry out a "thorough review".
UNIFIL peacekeepers in Lebanon are on the frontline of the Israel-Hezbollah war, which has killed more than 1,200 people in Lebanon since September 23, according to an AFP tally of Lebanese health ministry figures.
Four peacekeepers have been injured including two Indonesians who were hurt on Thursday when a tank shot at their watchtower, according to UNIFIL.
Diplomatic efforts to negotiate an end to the fighting have so far failed, but Lebanese Prime Minister Najib Mikati said his government would ask the UN Security Council to issue a new resolution calling for a "full and immediate ceasefire".
Lebanon's military said on Friday that an Israeli strike on one of its positions in south Lebanon killed two soldiers.
In a show of support for Iran's ally Hezbollah, the speaker of the Iranian parliament Mohammad Bagher Ghalibaf visited on Saturday the site of a deadly Israeli strike earlier this week that, according to a source close to Hezbollah, targeted Hezbollah's security chief Wafiq Safa.
Neither Hezbollah nor Israel has confirmed whether Safa was indeed the target of the strike, but according to the Lebanese health ministry, the raid killed 22 people.
The visit to Lebanon, a signal of defiance, comes after Israel vowed to respond to Iran's second-ever direct attack.
Israeli Defence Minister Yoav Gallant vowed this week that his country's response would be "deadly, precise and surprising".
The United States is pushing for a "proportionate" response that would not tip the region into a wider war, with President Jore Biden urging Israel to avoid striking Iranian nuclear facilities or energy infrastructure.
Gaza deaths
Iran-backed Hezbollah began firing on Israel in support of its Palestinian ally Hamas following the October 7, 2023 attack on Israel which resulted in the deaths of 1,206 people, mostly civilians, according to an AFP tally based on official Israeli figures, which includes hostages killed in captivity.
Israel's military campaign in Gaza has wrought devastation and, according to data from the health ministry in the Hamas-run territory, killed 42,175 people, a majority civilians.
Israeli operations in Gaza continue, with the army laying siege to an area around Jabalia in the north, causing more suffering for hundreds of thousands of people trapped there, according to the UN agency for Palestinian refugees.
"The bombardment has not stopped. Every minute there are shells, rockets and fire on the buildings and everything that moves", Areej Nasr, 35, told AFP after fleeing from Jabalia to Gaza City Thursday.
On Friday, Gaza's civil defence agency reported 30 people killed in Israeli strikes in the area, including on schools being used as shelter by displaced people.
An AFP journalist in Gaza reported heavy artillery shelling, explosions and gunfire Saturday further south in Gaza City's Zeitoun neighbourhood.
Adraee, the Israeli military spokesman, on Saturday posted another evacuation warning for an area near Jabalia.
"The specified area, including the shelters within it, is considered a dangerous combat zone," Adraee said on X, ordering residents to move to the humanitarian zone in the southern part of the strip.
