Israeli strikes killed 42 Palestinians in the Gaza Strip on Sunday, the worst daily toll in almost a week of deadly clashes, as UN Security Council talks fizzled despite global alarm at the escalating conflict.

Israeli warplanes continued to pummel the Palestinian enclave overnight Sunday to Monday, carrying out dozens of air strikes across the densely populated territory in just a few minutes and causing power cuts, AFP journalists said.

Israeli seurity forces advance amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Israeli seurity forces advance amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Photo: AFP / Ahmad GHARABLI

The Israeli army said in the first hours of Monday its fighter jets were "striking terror targets in the Gaza Strip".

UN Secretary-General Antonio Guterres pleaded for an immediate end to the "utterly appalling" violence and warned of an "uncontainable security and humanitarian crisis".

Map of Jerusalem's Old City Map of Jerusalem's Old City Photo: AFP / AFP

But the council meeting, already delayed by Israel's ally the United States, resulted in little action.

The heaviest exchange of fire in years -- sparked by unrest in Jerusalem -- has killed 197 in Gaza and 10 in Israel since Monday, 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 the coastal enclave, where an Israeli strike that destroyed a building housing journalists' offices sparked international outrage.

Israeli security forces form a shield as a stun grenade bursts amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Israeli security forces form a shield as a stun grenade bursts amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Photo: AFP / Ahmad GHARABLI

The death toll kept rising in Gaza as rescuers extracted bodies from vast piles of smoking rubble and the bereaved wailed in grief.

"We were sleeping and then all of a sudden there were rockets raining down on us," said Lamia al-Koulak, 43, who lost relatives in a dawn bombardment.

An injured Palestinian protestor is helped during clashes with Israeli police in Sheikh Jarrah in east Jerusalem An injured Palestinian protestor is helped during clashes with Israeli police in Sheikh Jarrah in east Jerusalem Photo: AFP / EMMANUEL DUNAND

"The children were screaming. For half an hour we were bombarded without prior warning. We came out to find the building next door flattened."

Israeli Prime Minister Netanyahu said the campaign would "take time" to finish.

Israeli security forces deploy next to the Dome of the Rock mosque amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Israeli security forces deploy next to the Dome of the Rock mosque amid clashes with Palestinian protesters at the al-Aqsa mosque compound in Jerusalem Photo: AFP / Ahmad GHARABLI

"Our campaign against the terrorist organisations is continuing with full force," he said in a televised address. "We are acting now, for as long as necessary, to restore calm and quiet to you, Israel's citizens."

Masked Palestinian supporters of Islamic Jihad prepare incendiary balloons near Beit Lahia in Gaza City, to launch across the border fence towards Israel Masked Palestinian supporters of Islamic Jihad prepare incendiary balloons near Beit Lahia in Gaza City, to launch across the border fence towards Israel Photo: AFP / MAHMUD HAMS

Israel's army said about 3,000 rockets had been fired since last Monday from Gaza towards Israel -- the highest rate ever recorded.

Around 450 fell within the coastal strip, while the Iron Dome anti-missile system intercepted over 1,000, according to the army.

Israeli mounted policemen disperse protesters during a demonstration by Palestinians against the possible eviction of Palestinian families from their homes in Sheikh Jarrah Israeli mounted policemen disperse protesters during a demonstration by Palestinians against the possible eviction of Palestinian families from their homes in Sheikh Jarrah Photo: AFP / Menahem KAHANA

Rockets have wounded over 280 people, hitting districts previously well beyond the range of Hamas' rockets.

Army chief Aviv Kochavi said Israel had reacted with unprecedented force.

Palestinian faithful hold night-time prayers in front of the Dome of the Rock in the Old City of Israeli-annexed east Jerusalem Palestinian faithful hold night-time prayers in front of the Dome of the Rock in the Old City of Israeli-annexed east Jerusalem Photo: AFP / Ahmad GHARABLI

"Hamas misjudged the strength of our response," he said.

Two doctors and at least 58 children have died in Gaza, local health authorities said. More than 1,200 people have been wounded and entire city blocks smashed to rubble.

Gaza health authorities said 40,000 people had been displaced from their homes, and the head of the UN agency for Palestinian refugees, Philippe Lazzarini, announced over 40 of UNRWA's schools had been converted into shelters.

An Israeli sapper checks a damaged apartment in the southern Israeli city of Ashkelon after rockets were fired by the Hamas movement from the Gaza Strip towards Israel overnight An Israeli sapper checks a damaged apartment in the southern Israeli city of Ashkelon after rockets were fired by the Hamas movement from the Gaza Strip towards Israel overnight Photo: AFP / JACK GUEZ

Save the Children warned that life-saving services were "at breaking point" after Israeli strikes damaged power lines.

The Israeli army says it takes all possible precautions to avoid harming civilians, and blames Hamas for deliberately placing military targets in densely populated areas.

Relatives of Palestinian Hussein al-Titi, 26, killed by Israeli gunfire in Fawwar refugee camp near the city of Hebron, in the occupied West Bank, mourn over his body Relatives of Palestinian Hussein al-Titi, 26, killed by Israeli gunfire in Fawwar refugee camp near the city of Hebron, in the occupied West Bank, mourn over his body Photo: AFP / HAZEM BADER

Palestinian foreign minister Riyad al-Maliki urged the Security Council to act, accusing Israel of "war crimes and crimes against humanity".

But Israel's UN ambassador blamed Gaza militants for the bloodshed.

"It was completely premeditated by Hamas in order to gain political power," Gilad Erdan said.

The Israeli army said it had targeted the infrastructure of Hamas and Islamic Jihad, including a vast tunnel system, weapons factories and storage sites.

Israeli air strikes also hit the home of Yahya Sinwar, head of Hamas's political wing in Gaza, the army said, releasing footage of plumes of smoke and intense damage, but without saying if he was killed.

Balls of flame and a cloud of debris shot into the sky Saturday afternoon as Israel's air force flattened a building housing Al Jazeera and AP news agency, after giving journalists an hour to evacuate.

Netanyahu on Sunday defended the strike, alleging the building also hosted a Palestinian "terrorist" intelligence office.

AP called for an independent investigation. Al Jazeera's Jerusalem bureau chief, Walid al-Omari, accused Israel of trying "to silence media that are witnessing, documenting and reporting the truth".

Media watchdog Reporters Without Borders called on the International Criminal Court to determine whether the strike on a building housing media outlets constitutes war crimes.

The cross-border fire has sparked 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 Monday.

A rocket on Sunday damaged a synagogue in the southern Israeli city of Ashkelon, shortly before prayers for the Shavuot Jewish holiday.

And a car-ramming attack wounded seven police officers in the flashpoint Sheikh Jarrah neighbourhood of Israeli-annexed east Jerusalem, police said, adding that the attacker had been "neutralised".

Sheikh Jarrah has been at the heart of the flare-up, seeing weeks of clashes between Palestinians and Israeli security forces who have cracked down on protests against the planned expulsion of several Palestinian families from their homes there.

Palestinians have also been outraged by police actions against worshippers protesting at Jerusalem's Al-Aqsa mosque compound.

China on Sunday accused the US of blocking a Security Council statement on the violence.

"Simply because of the obstruction of one country, the Security Council hasn't been able to speak with one voice," said Foreign Minister Wang Yi.

The United States, Israel's main ally, had already delayed the Council session and shown little enthusiasm for a resolution.

President Joe Biden's administration says it is working behind the scenes and that a Security Council statement could backfire.

The Biden administration has publicly backed Israel's right to self-defence, while urging de-escalation.