Israeli strikes killed 40 Palestinians in the Gaza Strip Sunday, the worst reported daily death toll yet in the almost week-long clashes, as the UN Security Council prepared to meet amid global alarm at the escalating conflict.
The heaviest fighting in years, sparked by unrest in Jerusalem, saw the rivals again trade heavy fire, with the death toll rising to 188 in the crowded coastal enclave of Gaza since Monday and at 10 in Israel, according to authorities on either side.
Israel said Sunday morning its "continuing wave of strikes" had in the past 24 hours struck over 90 targets across Gaza, where the destruction of a building housing news media organisations sparked an international outcry.
In Gaza, the death toll kept rising as emergency teams worked to pull out bodies from vast piles of smoking rubble and toppled buildings, as relatives wailed in horror and grief.
UN Secretary-General Antonio Guterres was "dismayed" by civilian casualties in Gaza and "deeply disturbed" by Israel's strike on Saturday on the tower housing the Associated Press and Al Jazeera bureaus, a spokesperson said.
Israel's army said Sunday that about 3,000 rockets had been fired from the coastal strip towards Israel -- the highest rate ever recorded -- of which about 450 failed launches fell in the Gaza Strip.
Israel's Iron Dome anti-missile system had intercepted over a thousand rockets, the army said, in almost a week during which Israeli residential buildings have been hit, with over 280 people suffering physical injuries.
"The intensity of the conflict is something we have not seen before, with non-stop airstrikes in densely populated Gaza and rockets reaching big cities in Israel," said the International Committee of the Red Cross.
"As a result, children are dying on both sides."
Pope Francis said the violence risked degenerating further "into a spiral of death and destruction" and said: "Where will hatred and revenge lead? Do we really think we will build peace by destroying the other?"
The bloodiest military conflict in seven years has also sparked a wave of inter-communal violence between Jews and Arab-Israelis, as well as deadly clashes in the occupied West Bank, where 19 Palestinians have been killed since last Monday.
The Israel Defense Forces (IDF) said it had targeted the infrastructure of Hamas and Islamic Jihad, including by pounding a vast tunnel system, weapons factories and storage sites.
Israeli air strikes also hit the home of Yahya Sinwar, head of Hamas' political wing in the Gaza Strip, the army said, releasing a video showing plumes of smoke and intense damage, but without saying if he was killed.
At least 55 children have lost their lives in Gaza, local health authorities said, more than 1,200 people have been wounded and entire buildings and city blocks reduced to rubble.
The IDF says it takes all possible precautions to avoid harming civilians and has blamed Hamas for deliberately placing military targets in densely populated areas.
One strike on Gaza Saturday killed 10 members of an extended family.
The children "didn't carry weapons, they didn't fire rockets", said Mohammad al-Hadidi, one of the grieving fathers.
Some 10,000 Gazans have fled their homes near the Israeli border for fear of a ground offensive, the UN said.
"They are sheltering in schools, mosques and other places during a global Covid-19 pandemic with limited access to water, food, hygiene and health services," UN humanitarian official Lynn Hastings said.
Balls of flame and a cloud of debris shot into the sky Saturday afternoon as Israel's air force flattened the 13-floor Gaza building housing Al Jazeera and AP news agency, after giving a warning to evacuate.
Al Jazeera's Jerusalem bureau chief, Walid al-Omari, told AFP: "It is clear that those who are waging this war do not only want to spread destruction and death in Gaza, but also to silence media that are witnessing, documenting and reporting the truth."
AP President and CEO Gary Pruitt said he was "shocked and horrified" by the attack.
Israeli defence officials said the building housed not only news bureaus but offices of Hamas militants.
AFP Chairman Fabrice Fries said the agency "stands in solidarity with all the media whose offices were destroyed in Gaza" and called on all parties "to respect the media's freedom to report on events".
The UN Security Council was due to meet at 1400 GMT Sunday.
Israel ally Washington, which had blocked a UNSC meeting scheduled for Friday, has been criticised for not doing enough to stem the bloodshed.
US President Joe Biden again underscored Israel's right to defend itself in a phone call with Israeli Prime Minister Benjamin Netanyahu but also expressed his "grave concern" over the violence as well as for the safety of journalists.
US Secretary for Israel-Palestinian Affairs Hady Amr was to hold talks Sunday with Israeli leaders before meeting Palestinian officials.
The escalating conflict was sparked by unrest in Jerusalem that had simmered for weeks and led to clashes between riot police and Palestinians, fuelled by anger over planned Israeli expulsions of Palestinians in the Sheikh Jarrah neighbourhood of east Jerusalem.
Palestinian foreign minister Riyad al-Maliki criticised the countries that had moved to normalise relations with Israel last year, the United Arab Emirates, Bahrain, Sudan and Morocco.
Normalisation "without achieving peace and ending the Israeli occupation of Arab and Palestinian lands represents support for the apartheid regime and participation in its crimes," Maliki told an emergency meeting of the Organisation of Islamic Cooperation.
In Gaza, Abu Anas Ashkhani said his sister-in-law and four of his nephews, the oldest just 11, were killed while they were sleeping early Sunday in a strike on their home in the Al-Rimal neighbourhood.
"I was in the house next door," he said when, just after midnight, "there was a strike and it was hell. We went around to see what happened. It was surreal. The mother and the children were pulled out from the rubble."