The death toll surged to almost 1,000 since Palestinian militant group Hamas launched its massive surprise attack on Israel with a barrage of rockets and a large-scale ground assault, officials on both sides said Sunday.
The conflict`s worst escalation in decades has claimed more than 600 lives on the Israeli side, the government press office said, while Gaza officials reported at least 370 deaths, with thousands more wounded on each side.
Thousands of Israeli forces were deployed to battle holdout Hamas fighters in the south and the airforce again pounded targets in the Gaza Strip as Israeli Prime Minister Benjamin Netanyahu warned of a "long and difficult" war ahead.
Gun battles raged in towns and on highways as the Israeli army sought to secure desert regions near the coastal enclave, rescue Israeli hostages and evacuate all areas near Gaza within 24 hours.
"We`ll reach each and every community until we kill every terrorist in Israel," vowed military spokesman Daniel Hagari, a day after hundreds of Hamas fighters launched their shock offensive and surged into Israel using vehicles, boats and even motorised paragliders.
There was widespread shock and dismay in Israel after at least 100 citizens were captured by Hamas gunmen and abducted into Gaza, with images circulating on social media of bloodied hostages, and distraught relatives pleading for the state to rescue them.
Yifat Zailer, 37, said she was horrified to see online video footage from inside Gaza that showed her female cousin and the woman`s children, aged nine months and three years.
"That`s the only confirmation we have," she told AFP by phone, her voicing breaking with emotion, and adding there was no information on her cousin`s husband and her elderly parents.
"After the army took control of the kibbutz, they weren`t at home," she said. "We assume they were kidnapped ... We want to know what their condition is, we want them to return safe. They`re innocent civilians."
Israel also came under attack from the north when Lebanon`s Hezbollah launched guided missiles and artillery shells Sunday "in solidarity" with the unprecedented Hamas offensive, without causing any casualties.
Israel responded with artillery strikes across the UN-patrolled border. "We recommend Hezbollah not to come into this," said army spokesman Richard Hecht. "If they come, we are ready."
Israel was stunned when Hamas launched their multi-pronged offensive at dawn Saturday, the Jewish Sabbath, raining down thousands of rockets as fighters infiltrated towns and kibbutz communities and stormed an outdoor rave party held under the desert sky.
Panicked Israeli residents phoned media outlets as they hid out in their homes from militants going door to door and shooting civilians or dragging them away.
Two Thai nationals were among those killed, and other Asian nationals, many of whom work as farm labourers in the region, were believed to be among the hostages.
"A lot of people have been killed," said Hecht, after the military released the names of 26 fallen soldiers. "We lost soldiers, lost commanders and lost a lot of civilians.
"We are completing efforts to retake full control of Israeli territory from Hamas," he added, reporting that the army had struck 426 Hamas targets including Gaza tunnels and buildings.
`No respite`
Global concern has mounted, with Western capitals condemning the attack by the Islamist group Hamas, which Washington and Brussels consider a terrorist group.
Israel`s foes have praised the assault, including Iran whose President Ebrahim Raisi spoke Sunday with leaders of Hamas and Islamic Jihad and voiced his support, according to official media in the Islamic republic.
Anti-Israel protests have flared in some other majority Muslim countries, and Germany and France were among nations stepping up security around Jewish temples and schools.
In the Egyptian city of Alexandria a police officer opened fire "at random" on Israeli tourists Sunday, killing two of them and their Egyptian guide before he was arrested.
Netanyahu -- who leads a hard-right coalition government but has received pledges of support from political opponents during Israel`s national emergency -- has vowed to turn Hamas hideouts "to rubble" and urged Palestinians there to flee.
"We are embarking on a long and difficult war that was forced on us by a murderous Hamas attack," Netanyahu wrote on X, formerly Twitter.
"The first stage is ending at this time with the destruction of the vast majority of the enemy forces that infiltrated our territory," he added, pledging no "respite" until victory.
US President Joe Biden has voiced "rock solid and unwavering" support for its key ally Israel and warned "against any other party hostile to Israel seeking advantage in this situation".
`Liberate our land`
Hamas has labelled its attack "Operation Al-Aqsa Flood" and called on "resistance fighters in the West Bank" and "Arab and Islamic nations" to join the battle.
Its attack came half a century after the outbreak of the 1973 Arab-Israeli war, called the Yom Kippur war in Israel, sparking bitter recriminations on what was widely seen as an enormous intelligence failure.
"There was a very bad failure here," said Sderot resident Yaakov Shoshani, 70. "The Yom Kippur War was small compared to it, and I was a soldier in the Yom Kippur War."
He recalled the terror of the attack on their town near Gaza.
"I held a kitchen knife and a large screwdriver, and I told my wife that, if something happens, to make sure to read the Kaddish (prayer) over me, if you stay alive," he said. "And so we stayed close to each other at home, shut everything and turned off the lights."
Hamas chief Ismail Haniyeh has predicted "victory" and vowed to press ahead with "the battle to liberate our land and our prisoners languishing in occupation prisons".
Hamas said Saturday it had fired 5,000 rockets, while Israel reported some 3,000 incoming projectiles. Several bypassed the Iron Dome missile defence system and smashed into buildings as far as Tel Aviv.
Israel rushed forces to the embattled south, called up reservists and hit Gaza in operation "Swords of Iron", with some observers predicting a possible ground invasion of Gaza.
Sderot resident Yitzhak, 67, said he expected the army to now "conquer Gaza house by house, clean the area there properly, and not leave Gaza until they get the very last rocket out of the ground."
Israeli attacks have reduced several Gaza residential towers to rubble in what Israel said were strikes aimed at Hamas facilities and which had followed warning calls for people inside to evacuate.
Another strike completely destroyed a mosque in Gaza`s Khan Yunis.
Hamas took control of Gaza in 2007, leading to Israel`s blockade of the impoverished enclave of 2.3 million people.
Israel and Hamas have fought several wars since, with the latest in May killing 34 Palestinians and one Israeli.
Many Gaza residents voiced defiance, with Mohammed Saq Allah, 23, saying: "We will not give up, and we are here to stay. This is our land, and we will not abandon our land."
The new war follows months of rising violence in the occupied West Bank and tensions around Gaza`s border and at contested holy sites in Jerusalem.
Before Saturday, the conflict had killed at least 247 Palestinians, 32 Israelis and two foreigners, including combatants and civilians, this year, according to Israeli and Palestinian officials.
Violence flared again in the West Bank Saturday, leaving at least seven Palestinians dead, said the health ministry in Ramallah.
UN Secretary-General Antonio Guterres urged "all diplomatic efforts to avoid a wider conflagration" and stressed that "only through negotiation leading to a two-state solution can peace be achieved".