Israeli warplanes and tanks pounded southern Gaza on Tuesday, and the UN said aid distribution to Gazans facing growing hunger had largely stopped because of the intensity of fighting in the two-month-old war between Israel and Hamas.
In the southern Gazan city of Rafah, which borders Egypt, health officials said 22 people including children were killed in an Israeli air strike on houses overnight. Civil emergency workers were searching for more victims under the rubble.
Residents said the shelling of Rafah, where the Israeli army this month ordered people to head for their safety, was some of the heaviest in days.
In Khan Younis, southern Gaza's main city, residents said tank shelling focused on the city centre.
Hundreds more civilians have been killed in Israel's assault on Gaza since the US on Friday vetoed a UN Security Council resolution calling for a ceasefire.
Aid agencies say hunger is worsening among Gazans, with the UN World Food Programme saying half of Gaza's population is starving.
The UN humanitarian office (OCHA) said on Tuesday limited aid distributions were taking place in the Rafah district, but "in the rest of the Gaza Strip, aid distribution has largely stopped over the past few days, due to the intensity of hostilities and restrictions of movement along the main roads".
Aid flows were also restricted by a shortage of trucks in Gaza, a continuing lack of fuel, communications blackouts, and growing numbers of staff unable to travel to the Rafah crossing with Egypt because of the intensity of hostilities, it said.
Israel's retaliatory assault has killed 18,205 people and wounded nearly 50,000, according to the Gaza health ministry.
UN officials say 1.9 million people - 85 per cent of Gaza's population - are displaced, and describe conditions in the southern areas where they have concentrated as hellish.
Displaced people sheltering in Rafah have erected tents of wood and nylon in open areas. Some are sleeping in streets.
To increase the aid reaching Gaza, Israel said on Monday it would add shipment screening at the Kerem Shalom border crossing, without opening the crossing itself.
Most trucks entered Gaza at this crossing before the war. Two Egyptian security sources said inspections would begin on Tuesday under a new deal between Israel, Egypt and the US.


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