Israel pounded Gaza City with relentless bombardments on Tuesday as it vowed a retaliation against the Hamas militant group that would “reverberate … for generations”.
The war — which began after Hamas militants stormed into Israel on Saturday, bringing gunbattles to its streets for the first time in decades — has already claimed at least 1,600 lives.
It is only expected to escalate from here, with questions over whether Israel will launch a ground invasion after expanding on a massive mobilisation of reservists and Hamas threatening to kill captured Israelis if strikes targeted civilians without warning.
Israel said that Hamas and other militant groups in Gaza are also holding more than 150 soldiers and civilians hostage.
Israel’s military said that it had regained effective control over its south and the border, which was breached over the weekend in an attack that caught its vaunted military and intelligence apparatus completely off guard.
The bodies of roughly 1,500 Hamas militants, meanwhile, were found on Israeli territory, the military said.
It was not immediately clear whether those numbers overlapped with deaths previously reported by Palestinian authorities.
The military expanded the mobilisation of reservists to 360,000, according to Israeli media.
That, along with the airstrikes and a formal declaration of war on Sunday, pointed to Israel increasingly shifting to the offensive against Hamas, threatening greater destruction in the densely populated, impoverished Gaza Strip.
It remains to be seen whether that offensive will include a ground assault. The last such assault was in 2014.
The Israeli military said it struck hundreds of targets in Gaza City’s Rimal neighbourhood, a densely populated, upscale district that is home to ministries of the Hamas-run government, as well as universities, media organisations and the offices of aid organisations.
After hours of non-stop strikes, some residents left their homes at daybreak to find buildings torn in half by strikes, while others were reduced to mounds of concrete and rebar.
Cars were flattened and trees burned out in moonscapes that had been residential streets.
“We have only started striking Hamas,” Israeli Prime Minister Benjamin Netanyahu said in a nationally televised address late on Monday.
“What we will do to our enemies in the coming days will reverberate with them for generations.”
The devastation in Rimal signalled what could be a new Israeli tactic: warning civilians to leave certain areas and then hitting those areas with airstrikes of unprecedented intensity.
If these types of bombardments continue, Gaza’s civilians will have fewer and fewer places to shelter as more neighbourhoods become uninhabitable.
The heavy bombardments and Israel’s threats to topple the group sharpened questions about Hamas’ strategy and objectives.
Hamas leaders have not spoken publicly about whether they anticipated Israel’s ferocious retaliation — and the potential risk of losing much of the group’s government infrastructure — when they launched the weekend attack.
In a briefing on Tuesday, army spokesperson Lt Col Richard Hecht suggested Palestinians should try to leave through the Rafah border crossing with Egypt.
The UN said that more than 187,000 of Gaza’s 2.3 million people have left their homes — the most since a 2014 air and ground offensive by Israel uprooted about 400,000 people.
UNRWA, the UN agency for Palestinian refugees, is sheltering more than 137,000 people in schools across the territory. Families have taken in some 41,000 others.
Asked if Israel considered Hamas’ civil government, such as parliament and ministries, legitimate targets, Lt Col Hecht said “if there’s a gunman firing rockets from there, it turns into a military target”.
In response to Israel’s aerial attacks, the spokesman of Hamas’ armed wing, Abu Obeida, said that the group will kill one Israeli civilian captive any time Israel targets civilians in their homes in Gaza “without prior warning”.
Israeli Foreign Minister Eli Cohen warned Hamas against harming any of the hostages, saying, “This war crime will not be forgiven.”
Mr Netanyahu appointed a former military commander to manage the hostage and missing persons crisis.
The Israeli military said more than 900 people already have been killed in Israel.
In Gaza and the West Bank, 704 people have been killed, according to authorities there; Israel says hundreds of Hamas fighters are among them. Thousands have been wounded on both sides.
The surprise weekend attack by Hamas left a death toll unseen since the 1973 war with Egypt and Syria.
That fomented calls to crush Hamas no matter the cost, rather than continuing to try to bottle it up in Gaza.
Israel is run by its most hard-right government ever, dominated by ministers who adamantly reject Palestinian statehood.
Israeli Defence Minister Yoav Gallant ordered a “complete siege” on Gaza, saying authorities would cut electricity and block the entry of food and fuel.
Jan Egeland, secretary general of the Norwegian Refugee Council aid group, warned that a siege would spell “utter disaster” for Gazans.
“There is no doubt that collective punishment is in violation of international law,” he told The Associated Press.
“If and when it would lead to wounded children dying in hospitals because of lack of energy, electricity and supplies, it could amount to war crimes.”
Hamas, in turn, says it is ready for a long battle to end an Israeli occupation it says is no longer tolerable.
Desperation has grown among Palestinians, many of whom see nothing to lose under unending Israeli control and increasing settler depredations in the West Bank, the blockade in Gaza and what they see as the world’s apathy.
Israeli airstrikes on Gaza have razed 790 housing units and severely damaged 5,330, the UN Office for the Co-ordination of Humanitarian Affairs said.
Damage to three water and sanitation sites has cut off services to 400,000.
The Israeli siege will leave Gaza almost entirely dependent on its crossing into neighbouring Egypt at Rafah, where cargo capacities are lower than other crossings into Israel.
An Egyptian military official said more than two tonnes of medical supplies from the Egyptian Red Crescent were sent to Gaza and efforts were underway to organise food and other deliveries.
Hamas has ruled Gaza since driving out forces loyal to the internationally recognised Palestinian Authority in 2007, and its rule has gone unchallenged through the blockade and four previous wars with Israel.
Meanwhile in the West Bank, Palestinians entered a fourth day under severe movement restrictions.
Israeli authorities have sealed off crossings to the occupied territory and closed checkpoints, blocking movement between cities and towns.
