Image source, EPA

There's another line or two still to bring you from that US briefing.

The White House believes there are 20 missing Americans following the Hamas attacks in Israel, says US National Security Advisor Jake Sullivan. But he says he can't confirm how many are hostages.

The US government is making it the "highest priority" to get information about the missing Americans and is in touch with all the families affected, Sullivan says.

Earlier, US President Joe Biden said 14 Americans were known to have been killed in the attacks.

Sullivan also reiterates the United States' commitment to Israel: "This is personal for the American people with their bond with the Israeli people."

Israel has launched numerous air strikes and shelled what it says are Hamas targets in the Gaza Strip following Saturday's surprise incursion by militants.

News agencies have been filing pictures showing the effects of military action in the area.

Image source, Reuters

Image source, Reuters

Image source, Mohamed Saber/EPA-EFE/REX/Shutterstock

Israeli forces say they successfully located - and rescued - 30 trapped people in the southern kibbutz of Ein HaShlosha late on Monday.

Officials received a "distress call" at around 21:00 local time (18:00 GMT), according to information shared by the Israel Defense Forces (IDF), and using coordinates were able to locate those trapped before 22:00.

It has not disclosed where the group were, but after Hamas launched its attack on Saturday, many residents are known to have fled their homes and in some cases attempted to hide.

The IDF released the following image of those who were trapped, after officials found them:

Image source, Israel Defense Forces

In a further show of its unequivocal support for Israel, the US State Department has just announced that the country's top diplomat, Secretary of State Antony Blinken, will travel to Israel "in the coming days".

Blinken will "engage our Israeli partners directly about the situation on the ground and how we can continue to best support them in their fight against the terrorists who launched these horrific attacks," the department said.

"Our support for Israel is unwavering."

Here's the full report from Jeremy Bowen, the BBC's international editor, who's visited a village said by the Israeli military to have witnessed a massacre by Hamas.

This video contains disturbing images.

US President Joe Biden says he has one word for those considering taking advantage of the conflict in the Middle East.

Sofia Bettiza
Reporting from Brussels

EU Foreign Policy Chief Josep Borrell has said the bloc opposes a total siege of Gaza.

“Israel has the right to defend itself, but that needs to be done accordingly with international law, humanitarian law. And some decisions are contrary to international law.”

Borrell spoke after an emergency meeting of EU foreign ministers.

“Some actions – like cutting electricity and food for civilians – are against international law,” he said.

EU foreign ministers are urging both sides to respect humanitarian law. “That means no blockage of water, food or electricity to the civil population in Gaza,” said Borrell.

He stressed that the EU considered Hamas a terrorist organisation, but that the Palestinian Authority was a different thing.

“Not all Palestinian people are terrorists. So a collective punishment would be unfair and unproductive. It would be against our interests, and against the interest of peace.”

Biden concludes his short speech by warning those who might try to take advantage of the conflict and asserts his nation's support of Israel.

"Let there be no doubt. The United States has Israel's back. We'll make sure the Jewish and Democratic State of Israel can defend itself, today, tomorrow, as we always have. It's as simple as that."

"Anyone thinking of taking advantage of this situation, I have one word: Don’t."

He leaves and does not answer any questions.

Image source, Reuters

US President Joe Biden begins his remarks by calling the attacks "an act of sheer evil".

He calls Hamas blood-thirsty, saying the events are reminiscent of the worst atrocities committed by Isis, otherwise known as the so-called Islamic State group, and condemns them for "more than 1,000 civilians slaughtered. Among them at least 14 American citizens."

"Hamas does not stand for the Palestinian people," Biden says. "They used Palestinian people as human shields."

"Sadly for the Jewish people, it's not new," he continues. "It's brought to the surface painful memories" of antisemitism over the last century.

The US president shares examples of some of the horrific stories coming out of the region: "Parents butchered using their bodies to protect their children... Reports of babies being killed... Women raped and paraded as trophies."

"We stand with Israel, we stand with Israel," Biden says.

He asserts Israel will have what it needs to respond to the attack.

US President Joe Biden is speaking now about the conflict. He is joined at the White House by Vice-President Kamala Harris and Secretary of State Antony Blinken.

You can stream live at the top of the page.

The United Nations (UN) humanitarian relief agency has called for an immediate release of all hostages in the conflict.

Its chief Martin Griffiths said in a statement that his call to all sides was "unequivocal":

Image source, White House

US President Biden, Vice-President Harris, and other senior administration officials have just concluded a call with Israeli Prime Minister Benjamin Netanyahu.

The president posted on social media, external that his team spoke to Netanyahu to "receive a situation update on the terrorist attack in Israel and to direct next steps."

"We connected with Prime Minister Netanyahu to discuss coordination to support Israel, deter hostile actors, and protect innocent people," he said.

We are expecting to hear from President Biden soon in a short address about the conflict.

We reported earlier that, two senior Hamas officials had been killed in air strikes in Gaza, according to the Israeli military.

In that post, we said Hamas had not yet confirmed the deaths of Zakaria Abu Muammar and Jawad Abu Shamal, members of the Hamas political bureau. It has since released a statement doing so.

Jeremy Bowen
International editor, reporting from Kfar Aza kibbutz

Image source, Oren Rosenfeld

The residents of the Israeli border communities expected periodic rocket attacks after Hamas seized control of Gaza in 2007.

They accepted the danger as the price of country life in a tight-knit community which still had traces of the pioneer spirit of early Zionist settlements.

Residents of Kfar Aza, and the other Israeli communities near Gaza, enjoyed good quality of life - despite the threat from Hamas rockets.

In the houses, lawns and open areas of the kibbutz, a concrete shelter was never more than a dash away.

All the houses also had reinforced safe rooms. They also had outside terraces, barbeques, swings for the children, and fresh air.

But no one - here in Kfar Aza or elsewhere in Israel - imagined Hamas would be able to breach Israel's defences and kill so many people.

The horror and rage of Israelis has been mixed with incredulity that the state and the military failed in its fundamental duty to protect its citizens.

Jeremy Bowen
International editor, reporting from Kfar Aza kibbutz

Kibbutz Kfar Aza shares the experience of its Israeli neighbours. It was taken by surprise.

Its first line of defence was the kibbutz guard, residents with military experience who patrolled the perimeter.

They were killed fighting the attackers on Saturday.

Their bodies were removed this morning from their positions in the centre of the kibbutz, and like the other Israeli dead wrapped in black plastic, carried in stretchers to a parking area and laid in a line waiting to be recovered.

Reporters have today been visiting the village of Kfar Aza - the site of a massace committed by Hamas near the border with Gaza.

Until this morning fighting was still going on in the kibbutz. That's why Israeli soldiers are only now collecting the bodies of residents who were murdered.

Soldiers told the BBC's International Editor Jeremy Bowen that Hamas stormed in, burning homes and killing families.

An Israeli officer said some of the dead had been beheaded.

Image source, Oren Rosenfeld

An Israeli army general has been giving details of what he calls a "massacre" at the Kfar Aza kibbutz in Israel, just a short distance from the boundary with the Gaza Strip.

"You see the babies, the mothers, the fathers, in their bedrooms, in their protection rooms and how the terrorist kills them," said Maj Gen Itai Veruv, as quoted by the Reuters news agency.

"It's not a war, it's not a battlefield. It's a massacre," he added.

Reuters reports that bodies of Hamas militants were found at the site, along with those of Israeli residents.

It is the fourth day of the conflict.

Israel says it has secured its boundary with Gaza, three days after Hamas broke through to launch an assault that has left more than 1,000 Israelis dead. Meanwhile, Israeli air strikes on the Gaza Strip have continued, with Palestinian authorities saying more than 800 people have been killed.

In today's episode of the 5 Minutes On podcast, the BBC's Dan Johnson in Jerusalem and Rushdi Abu Alouf in Gaza provide eyewitness reports of events on the ground.

Alice Cuddy
Reporting from Ashkelon

At our accommodation in Ashkelon, we are back in a shelter as sirens continue to ring out through the city followed by the sound of rockets.

People here are bracing for a long night, after being warned by Hamas to leave the southern Israeli city by 17:00 local time (15:00 BST). The latest two rounds of missiles came within 30 seconds of each other, with those who left the shelter quickly rushing back in.

We’re starting to see reports of injuries in the city, including one woman who was injured by glass and debris.

Lyse Doucet
Chief International correspondent

Diplomatic efforts are said to be intensifying to try to free some of the more than 100 hostages reportedly being held by Hamas.

The focus appears to be on a swap involving women and children - including Israelis and other nationals - in an exchange for Palestinian women and children in Israeli jails.

A diplomat briefed on the talks told the BBC that discussions were under way involving mediation by the Gulf state of Qatar, where some of Hamas’s political leaders are based.

The US was described as co-ordinating the process. It doesn’t include the Islamic Jihad group (PIJ) which has reportedly seized about 30 hostages.

Both Israel and Hamas have publicly denied any hostage negotiations are taking place. But a diplomatic source said the talks were gathering pace.

It's unfolding in a highly fluid situation fraught with risk. One source said he was hopeful but admitted neither side was ready for mediation on any of the wider issues as this war worsens.