Rescuers say they've found more than 250 bodies at the site of an Israeli music festival attacked by Hamas militants in an unprecedented assault on Saturday
The Israeli military says at least 700 people have died in the attacks overall, more than 2,000 were injured, and that a number of hostages are being held in Gaza
Retaliatory Israeli air strikes have killed at least 413 people in the Gaza Strip, with 2,300 wounded, according to the latest update from Palestinian officials
The US has announced more support for Israel by sending munitions and boosting forces in the region
The family of a British man serving in the Israeli military, Nathanel Young, say he was killed in an attack; several other nations have said their own citizens have died or been abducted
The wave of attacks launched by the Hamas militant group on Saturday morning was the biggest escalation between the two sides for decades
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According to the Reuters news agency, who are translating Netanyahu's statement, the Israeli prime minister goes on to say "our enemy will pay a price, the type of which it has never known".
Netanyahu says Israel is at war "and we will win".
We'll bring you more from his latest statement shortly.
Israel's Prime Minister Benjamin Netanyahu has said "we are at war" in a video posted on X, external, formerly Twitter.
Frank Gardner
Security correspondent
This is a colossal intelligence failure for Israel.
The country has one of the most extensive and sophisticated intelligence networks in the Middle East, both domestic and external.
It has informants embedded inside militant groups not just in the Palestinian territories but in Lebanon, Syria and elsewhere.
It has, in the past, been able to assassinate militant leaders either with precision drone strikes or even booby-trapped mobile phones.
And yet today, at the end of a Jewish holiday, it appears to have been caught asleep at the wheel.
Hamas has been able to plan and launch this carefully coordinated assault on Israel seemingly in total secrecy.
That Israel will retaliate with massive force is a given. But Israelis will now be asking why their nation’s spies failed to see this coming and warn the country accordingly.
Concluding their remarks, the Israeli military spokesman says that fighting is still ongoing at the Erez border crossing as well as at the Zikim base - a training base belonging to the Israel Defense Forces.
Israel's military spokesman is declining to comment about reports of Israelis being captured by Hamas, according to the Reuters news agency.
More from Reuters now. It is reporting Israel's military spokesman as saying that "thousands of reservists will be called up" in the wake of the earlier rocket attacks on Israel.
An Israeli military spokesman says Palestinians fired 2,500 rockets at Israel "with infiltrations from paragliders, sea and ground", according to the Reuters news agency.
The Israel Defense Forces says it is carrying out air strikes on Hamas targets in Gaza in response to the earlier "barrages of rockets" , externalfrom Gaza into Israel.
We've heard from a few hospitals in Israel about the number of people currently being treated after the surprise attacks earlier:
We will continue to update these numbers throughout the day.
Israel's defence minister says that Hamas has launched a war against Israel.
Yoav Gallant said in a statement: "Hamas has made a grave mistake this morning and launched a war against the State of Israel".
He added that IDF troops are "fighting against the enemy at every location" and "the State of Israel will win this war".
Image source, ReutersPalestinians celebrated in the Gaza Strip after dozens of Hamas gunmen appeared to have infiltrated southern Israel
Image source, ReutersPeople sheltered in buildings during the rocket attacks
Image source, Reuters
Image source, ReutersAt least one person was killed in the attacks
The Israel Defense Forces says it is declaring "a state of readiness for war” in response to the surprise attack from Gaza.
The defence minister has approved a call-up for military reservists.
The Israeli military has begun to carry out retaliatory airstrikes in the Gaza Strip and has warned that Hamas will pay a very heavy price.
Israel’s top-level security cabinet will hold a meeting at 1pm local time about the unexpected Hamas attack, the prime minister's office says.
Before the meeting, Prime Minister Benjamin Netanyahu is holding an assessment with security officials.
Rushdi Abualouf
Reporting from Gaza City
From my position on the rooftop I can see rockets flying from the east, the south, the north, from everywhere.
Hamas TV is saying that 2,000 more rockets were fired, in addition to the 5,000 that the Hamas chief commander announced at the beginning of this operation.
We are talking about two and a half hours of non-stop firing.
Image source, Reuters
Image source, EPA
Image source, EPARockets launched from Gaza streak across sky towards Israel
An initial report from the Israel Defense Forces (IDF), said that a "number of terrorists" had infiltrated Israeli territory from the Gaza Strip.
“Residents in the area surrounding the Gaza Strip have been asked to stay in their homes,” the army said in a statement.
In a statement on X, formerly Twitter, the IDF said: "Israelis across the country - on Shabbat and the holiday of Simchat Torah - woke up to sirens sounding and Hamas firing rockets at them from Gaza this morning.
“We will defend ourselves."
The office of Israeli Prime Minister Benjamin Netanyahu said security chiefs are due to meet.
Mohammed Deif, the leader of the Islamist militant group, said that 5,000 rockets had been fired into Israel early on Saturday to launch what he called “Operation Al-Aqsa Storm”.
“We’ve decided to say enough is enough,” Deif said.
“We have already warned the enemy before. The occupation committed hundreds of massacres against civilians. Hundreds of martyrs and wounded died this year due to the crimes of the occupation.
“We announce the start of Operation Al-Aqsa Flood, and we announce that the first strike, which targeted enemy positions, airports, and military fortifications, exceeded 5,000 missiles and shells.”
Yolande Knell
Middle East correspondent, Jerusalem
Shocking videos being shared on social media appear to show Palestinian militants shooting at passers-by in the streets of southern Israel.
There are reports of houses in Sderot having been taken over by gunmen from the Islamist group Hamas, which governs Gaza. The Israeli army had told local residents to stay in their homes following reports of an infiltration.
The intensity of the rocket fire – including longer-range missiles - began just after dawn at the end of the Sukkot holiday and has caught Israelis off guard. Large fires are burning in parts of southern Israel where rockets have hit.
A senior Hamas military commander announced the start of the operation in a broadcast on Hamas media, calling on Palestinians everywhere to fight.
The Israeli military has said it will defend Israeli civilians and that Hamas will pay a heavy price for its actions.
Dozens of gunmen from the Islamist militant group Hamas appear to have infiltrated southern Israel in a surprise attack and are currently at large with videos of shooting in the streets.
At least one Israeli woman has been killed by intense rocket fire from the Gaza Strip, Israeli medics say, with sirens going off as far away as Jerusalem. Stay with us for updates.