What we know about Israel's war with Hamas

Israel bombarded Hamas targets in the Gaza Strip on Tuesday as Prime Minister Benjamin Netanyahu warned his country's military campaign was only the start of a sustained war.

Netanyahu promised to "change the Middle East", with fears of a regional conflict growing amid clashes on the Lebanese border and expectations of an Israeli ground invasion of Gaza.

This is what we know about the conflict so far:

How the assault unfoldedHundreds of Hamas militants attacked Israel from around 6:30 am (0330 GMT) on Saturday, the Jewish holiday of Simchat Torah, in an assault that came 50 years after the outbreak of the 1973 Arab-Israeli war.

The Iran-backed Islamists fired thousands of rockets from Gaza into Israel and used explosives and bulldozers to break through the security fence around the blockaded Palestinian enclave.

Using motorbikes, pickup trucks, motorised gliders and speed boats, the militants streamed into Israel, targeting cities including Ashkelon, Ofakim and Sderot.

The gunmen unleashed a massacre at a music festival attended by hundreds of young Israelis and foreigners near Kibbutz Reim, close to Gaza.

Israel said Hamas took around 150 hostages. They include at least 11 Thais, two Mexicans and an unknown number of Americans and Germans.

How Israel is respondingIsrael declared war on Hamas on Sunday and has since unleashed thousands of air strikes on the militia's positions.

Defence Minister Yoav Gallant on Monday ordered a "complete siege" on Gaza, meaning "no electricity, no food, no water, no gas".

The military has massed tens of thousands of troops and heavy armour near Gaza, and called up 300,000 reservists for a campaign it has dubbed "Swords of Iron".

Netanyahu vowed to reduce to "rubble" Hamas's hideouts in Gaza, an impoverished territory of 2.3 million people hemmed in by an Israeli-Egyptian blockade for more than 15 years.

Israeli air strikes pounded Gaza again on Tuesday, with the army saying it had "more or less restored control over the border" and was evacuating communities near the frontier.

Hamas launched a wave of rockets at Ashkelon on Tuesday, with at least one getting through Israeli air defences and hitting a residential area.

Its armed wing, the Ezzedine al-Qassam Brigades, on Monday said Israeli air strikes had killed "four of the enemy's prisoners", in a claim that could not be independently verified.

On Tuesday, the journalist syndicate in Gaza said four Palestinian journalists were killed by an Israeli air strike.

There have also been repeated border clashes between Israeli forces and Lebanon's Iran-backed Shiite militant group Hezbollah.

Three Israeli strikes have hit the Rafah crossing with Egypt, the only entry point into Gaza not controlled by Israel. 

Death toll mountsIsrael says Hamas gunmen have killed more than 900 people and wounded over 2,000 in Israeli cities, towns and kibbutz communities.

AFP journalists have seen the bullet-riddled bodies of civilians on the streets in locations including Sderot, the nearby kibbutz of Gevim and Zikim beach north of Gaza.

In the kibbutz of Beeri alone, Hamas gunmen killed more than 100 people, a volunteer who helped recover the bodies told AFP.

An estimated 270 people were killed at the Supernova music festival near Kibbutz Reim.

On the Gaza side, health officials said 900 people had been killed and more than 4,000 wounded.

On Tuesday, the Israeli military said it had found the bodies of 1,500 Islamist militants in the southern areas that it recaptured.

Eighteen Thais, 10 Nepalis, 14 US citizens and at least eight French nationals are among the foreigners killed.

Unrest has also broken out in the occupied West Bank where 15 Palestinians have died since Saturday.

What Hamas says about the attackHamas said it fired 5,000 rockets in an offensive it branded "Operation Al-Aqsa Flood".

Its chief Ismail Haniyeh on Saturday vowed to press ahead with "the battle to liberate our land and our prisoners languishing in occupation prisons".

Hamas has called on "resistance fighters in the West Bank" as well as in "Arab and Islamic nations" to join the battle.

On Monday it ruled out negotiating a prisoner swap with Israel as "the military operation is still ongoing".

It later threatened to start killing hostages every time Israel launches a strike on a civilian target without warning.

What both sides' allies are doingThe United States has vowed "rock solid and unwavering" support for Israel, with President Joe Biden ordering "additional support" for its key ally.

The US Navy moved an aircraft carrier battle group to the eastern Mediterranean to boost deterrence against new actors joining the conflict.

A joint statement by the United States, Britain, France, Germany and Italy condemned the attack and stressed their full support for Israel.

They said they "recognise the legitimate aspirations of the Palestinian people" but said Hamas "offers nothing for the Palestinian people other than more terror and bloodshed".

Iran has repeatedly denied allegations it had a role in Hamas's attack.

Lebanon's Hezbollah, an ally of Hamas, said it launched projectiles into northern Israel and Israel hit back with shelling on Tuesday, in the third successive day of cross-border fire.

In Monday's exchange, Israel's army said it killed a number of armed suspects who crossed the border from Lebanon and that its helicopters carried out strikes in the area.

How the world has reactedUnited Nations Secretary-General Antonio Guterres condemned "in the strongest terms" Hamas's attack on Israel and called for "diplomatic efforts to avoid a wider conflagration".

He said he was "deeply distressed" by the siege announcement and warned Gaza's already dire humanitarian situation would "only deteriorate exponentially".

The UN's human rights chief, Volker Turk, said Israel's cutting off of supplies to Gaza was banned under international law.

The European Union said it was reviewing development aid payments to Palestinians, after a row broke out between member states over suspending payments.

Russia said creating a Palestinian state was the "most reliable" solution for peace in Israel and that fighting terrorism alone would not ensure security.

Turkish President Recep Tayyip Erdogan, who strongly backs the Palestinian cause, urged both sides "to support peace".