Israel began calling up police and Army reservists on Saturday after separate attacks killed three persons, including an Italian tourist, in Tel Aviv and the occupied West Bank.
Despite appeals for restraint, violence has surged since the Israeli police clashed with Palestinians inside Jerusalem's flashpoint Al-Aqsa mosque on Wednesday, with Israel bombarding both Gaza and Lebanon in response to rocket fire by Palestinian militants.
The Italian was killed and seven other tourists wounded when an Israeli Arab ploughed a car into pedestrians on the Tel Aviv seafront on Friday evening and flipped over before being shot dead, the police and emergency services said.
Italian Prime Minister Giorgia Meloni named the dead man as Alessandro Parini, 36.
The police identified the driver as a 45-year-old from the Arab town of Kfar Kassem in central Israel.
"The terrorist was neutralised," a spokesman told AFP.
Palestinian Islamist movement Hamas, which rules Gaza, said the attack was a "natural and legitimate response" to Israel's "aggression" in the Al-Aqsa mosque.
Earlier on Friday, two British-Israeli sisters aged 16 and 20 were killed, and their mother seriously wounded when their car was fired on in the Jordan Valley in the occupied West Bank.
The Army said it had launched a manhunt for the perpetrators.
Following the Tel Aviv attack, Prime Minister Benjamin Netanyahu instructed the police to "mobilise all reserve border police units" and directed the army to "mobilise additional forces", his office said.
The police said four reserve battalions of border police would be deployed in city centres from Sunday, in addition to units already deployed in the Jerusalem region and in the central city of Lod, which has a mixed population of Jews and Arabs.
In the West Bank, Israeli troops came under fire in a drive-by shooting in the northern town of Yabad overnight, the army said on Saturday.
One hit was identified among the assailants, an army statement said.
Friday's attacks came after Israel launched air strikes and an artillery bombardment before dawn in response to rocket fire from the Gaza Strip and Lebanon.
It was the heaviest rocket fire from Lebanon since Israel fought a 34-day war with Iran-backed militant group Hezbollah in 2006 and the first time Israel has confirmed an attack on Lebanese territory since April 2022.
Israel "struck targets, including terror infrastructures, belonging to the Hamas terrorist organisation in southern Lebanon", the army said.
The Lebanese army said it had found and dismantled a multiple rocket launcher in an olive grove in the Marjayoun area near the border, still loaded with six primed rockets.
In Gaza, the Israeli army said it had hit two tunnels and "two weapon manufacturing sites" in response to the "security violations of Hamas".
It said air defences had intercepted 25 rockets from Lebanon on Thursday, while five had hit Israeli territory.
Israel "will not allow the Hamas terrorist organisation to operate from within Lebanon", it said.
The United Nations Interim Force in Lebanon (UNIFIL), which patrols the area along the border, urged restraint, noting: "Both sides have said they do not want a war."
On Friday evening, the army said it had shot down a drone that had entered Israel's airspace from Lebanon.
On Wednesday, Israeli riot police stormed the prayer hall of Al-Aqsa mosque in a pre-dawn raid, aiming to dislodge "law-breaking youths and masked agitators" they said had barricaded themselves inside.
Ramadan coincided with the Jewish Passover holiday this year raising tensions with the tens of thousands of Palestinians who pray at the Al-Aqsa mosque during the Muslim fasting month.
The Palestinians fear Netanyahu's hard-right government may change longstanding rules that allow Jews to visit but not pray in the mosque compound, despite his repeated denials.
The upsurge of violence drew condemnation from the European Union and the United States.
"The targeting of innocent civilians of any nationality is unconscionable," said State Department spokesman Vedant Patel.
"The European Union expresses its total condemnation of these acts of violence," said its foreign policy chief Josep Borrell.
A Qatari official said Doha was mediating between Israel and the Palestinians.
Qatar -- which has acted as a broker in previous understandings between Israel and Hamas -- "is working to deescalate the situation on all sides," the official said, speaking on condition of anonymity.
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