Gaza faces 'complete siege' as Israel responds to Hamas attacks

Israeli airstrikes continued on Monday as the country's military called up about 300,000 reservists ahead of a potential ground invasion of Gaza. Fighting between Israeli soldiers and Islamist Hamas militants continued in the border area with Gaza on Monday, as Israel's defence minister vowed a "complete siege" of the coastal strip.

United Nations Secretary-General Antonio Guterres urged restraint, acknowledging "Israel's legitimate security concerns" but expressing anguish that the "extremely dire" conditions for civilians in Gaza "will only deteriorate exponentially".

Israeli leaders, however, vowed massive and lengthy retaliation for the deadly attacks on Israel launched by Hamas from the Gaza strip on Saturday. Israeli gunships also launched strikes in southern Lebanon, raising fears in the region that the conflict could broaden and escalate further.

Prime Minister Benjamin Netanyahu said Israel's response "will change the Middle East".

"What Hamas will face will be harsh and terrible," Netanyahu said on Monday during a meeting with officials from towns in southern Israel, according to a statement. "We are only at the beginning." He called on the opposition to enter an emergency government. "We are engaged in a mission for our homeland, a war to secure our existence, a war that we will win," he said in a televised speech.

Netanyahu declared the divisions among Israelis to be over: "We are all united."

At least 900 Israelis were killed and 2,600 wounded in the Hamas attacks on Saturday in what was the worst civilian bloodbath in the country's history, according to the latest count by Israeli authorities. More than 4,500 rockets have since been fired at Israel, according to official figures.

Repeated Israeli strikes on densely populated Gaza, meanwhile, killed at least 687 people and left more than 3,800 injured, according to the health ministry there.

Hamas militants took at least 150 people captive and brought them back to Gaza, including women, children and the elderly. In addition to Israelis, citizens of a number of other countries are believed to be among the captives.

A Hamas spokesman threatened on Monday that the group would execute one hostage for every unannounced Israeli strike on Gaza. Earlier, the militant group had offered to trade a number of kidnapped elderly Israeli women for the release of 36 imprisoned Palestinian women held in Israel.

The militant group seized sole control of Gaza by force in 2007.

United Nations spokesperson Stéphane Dujarric said about 13,000 UN employees were in the Gaza Strip and a further 4,000 staff were in the West Bank.

"They're obviously not able to leave.  They are focused on trying to do whatever they can to help the population within their mandate," he said.

The Israeli military, meanwhile, reported that forces have regained control over villages near the Gaza Strip and had stopped the flow of militants across the border, although clashes with Hamas attackers continued in rural areas in Israel.

Hundreds of Hamas militants have been captured, and hundreds more killed in Gaza and along the border fence, a military spokesman said on Monday evening.

Israel's army instructed people in the country to stock up on food, water and medicine to last at least 72 hours. Citizens should also obtain other equipment for emergency situations and check where the nearest air raid shelter is, it said.

Violence between Israeli forces and Palestinians continued in the occupied West Bank on Monday.

Three Palestinians, including an 18-year-old who tried to ram a settlement with a tractor, were killed in clashes with the Israeli army, according to the Palestinian Health Ministry in Ramallah.

A 16-year-old also died from his injuries after a confrontation with soldiers on Sunday.

Along Israel's northern border with Lebanon, the Shia militant group Hezbollah, meanwhile, launched missiles into Israel on Monday evening after Israeli strikes in Lebanon killed three Hezbollah fighters.

The Israeli army had attacked targets in southern Lebanon after soldiers shot several militants trying to infiltrate Israeli territory from the Lebanese side.

Lebanese security sources told dpa that they suspect the militants involved were Palestinians. Hezbollah, which is closely allied with Iran, denied involvement: "We are not involved in such a clash."

Hezbollah did claim responsibility on Sunday for rockets fired from south-eastern Lebanon into Israeli-occupied border territory. Local television in Lebanon on Monday evening showed dozens of cars filled with people fleeing from areas close to Tyre near the border as Israeli shelling resumed.

Israeli President Isaac Herzog demanded that the world condemn Hamas and support Israel as the country "continues to endure a savage attack from a cruel and inhumane enemy".

In a video address on Monday evening, Herzog evoked the murder of European Jews during World War II to describe the attack by Hamas, saying that "not since the Holocaust have so many Jews been killed in one day".

Defence Minister Yoav Gallant, meanwhile, said Israel will impose a "complete siege" on the Gaza Strip.  Gallant said there will be "no electricity, no food, no fuel".

Energy Minister Israel Katz ordered water supplies to Gaza to also be cut. Groundwater in Gaza is severely salinated.

The situation is likely to deteriorate further for the approximately 2 million predominantly poor residents of the Gaza Strip, which stretches for about 40 kilometres along the Mediterranean Sea.

The World Health Organization (WHO) said the conflict was "compounding an already dire situation" in the Gaza Strip.

"Power outages and shortages of medicines and health supplies in Gaza Strip hospitals are hindering the delivery of life-saving medical care," the organisation said in a statement.

It said 11 attacks on health care services, including hospitals, ambulance and staff, had been recorded by the WHO since Saturday.

"There is an urgent need to establish a humanitarian corridor for unimpeded, life-saving patient referrals and movement of humanitarian personnel and essential health supplies," the WHO said.

Humanitarian aid supplies are being prepared from Egypt, with hospitals and ambulances on standby, said a Palestinian spokesman at the Rafah border crossing between Egypt and southern Gaza.

In Israel, the shocking scale of the coordinated attacks launched by Hamas, and the slow response by Israel's military, have raised serious questions about what failures might have allowed the attack.

Netanyahu on Monday denied reports in several Israeli media outlets that he had been explicitly warned by Egypt of an imminent attack from the Gaza Strip.

Egyptian intelligence chief Abbas Kamel had warned Netanyahu 10 days before the terror attack that "something unusual, a terrible operation" was to be expected from the Gaza Strip, the reports said.

Netanyahu's office called the reports "totally fake news", and said he had not spoken or met with Kamel – either directly or indirectly – since forming his current coalition government late last year.    (dpa)