The northern Israeli port city of Haifa was hit by about five rockets fired by the Lebanese armed group Hezbollah late on Sunday, causing damage and injuring eight people, Israeli authorities say.
A spokesman for Haifa's municipality said it was the first time the city had been targeted since the 2006 war between Israel and Hezbollah.
The Israeli military said it was investigating how its air defences failed to intercept the rockets. Hezbollah said it targeted a military base south of Haifa.
Another person was injured when a barrage of rockets hit the town of Tiberias, which is located to the east on the shore of the Sea of Galilee.
Meanwhile, Israeli warplanes carried out a new round of air strikes in the Lebanese capital. Beirut, hitting what the military said were Hezbollah targets.
The military also said a third division had joined its invasion of southern Lebanon, where Hezbollah said its fighters were targeting Israeli troops in and around border villages.
Israel’s government has pledged to make it safe for tens of thousands of displaced residents to return to their homes near the Lebanese border after a year of cross-border fighting sparked by the Gaza war.
The hostilities have escalated steadily since Hezbollah began firing rockets into northern Israel in support of Palestinians on 8 October 2023, the day after its ally Hamas’s deadly attack on southern Israel.
Hezbollah has remained defiant despite suffering a series of devastating blows in recent weeks, insisting on Monday that it was confident in its ability to “repel the [Israeli] aggression”.
According to the Israel Defense Forces (IDF), Hezbollah fired more than 135 rockets into northern Israel on Sunday.
Approximately five projectiles crossed from Lebanon after air raid sirens sounded in the Carmel and Bay areas of Haifa at 23:22 local time (20:22 GMT), an IDF statement said.
“Interceptors were fired. Fallen projectiles were identified in the area. The incident is under review,” it added.
Eliran Tal, spokesman for the Haifa municipality, told the BBC that two neighbourhoods were hit.
BBC Verify geolocated CCTV footage showing the moment that one of the rockets hit a roundabout near a supermarket and several apartment blocks in the west of the city.
In another video, emergency services and bystanders are seen inspecting a crater and piles of rubble and earth at the scene.
Tal Rosen, a member of the emergency services, told Reuters news agency that he had been inside his home about 500m (1,640ft) away when he heard an explosion.
“In the beginning, we didn't find any injuries and then I saw in this building,” he said, pointing to damaged windows on the side of a nearby apartment block.
“There were shards of glass in this building. I went inside and I found four people [with] minor to moderate [injuries]."
Israel’s Magen David Adom (MDA) ambulance service said it treated a 13-year-old boy in a moderate condition with shrapnel injuries to his head, as well as a 22-year-old man in a moderate condition with both a blast injury and a head injury from falling through a window.
Hezbollah said it launched "a salvo of Fadi 1 rockets at the Carmel base south of Haifa” late on Sunday in retaliation for the Israeli air strike that killed its leader Hassan Nasrallah last month.
Mr Tal dismissed Hezbollah's claim, saying it was "an attack on civilian population".
He estimated that 95% of Haifa's population of 280,000 was staying put.
"With missile threats from the north, it is not an easy period of time. But we are strong," he said.
"We went through a lot of tragedy like this - and I hope the IDF and the leadership will do their best to push the enemy far from the border."
The MDA also reported that a man in his 20s was in a serious but stable condition and suffering from shrapnel injuries to his chest and abdomen following a separate rocket attack on the town of Tiberias, about 50km (30 miles) to the east.
The IDF said approximately 15 projectiles were identified as crossing from Lebanon at the same time as the Haifa attack. Some were intercepted while others fell in the area, it added.
The Israeli police said some buildings and properties were damaged.