People have also described digging down into the soil to access water pipes, for drinking and washing.

The UN has warned that acute malnutrition among young children in the north has risen sharply, and is now above the critical threshold of 15%.

The UN’s humanitarian coordination agency, Ocha, says more than half the aid missions to the north of Gaza were denied access last month, and that there is increasing interference from Israeli forces in how and where aid is delivered.

It says 300,000 people estimated to be living in northern areas are largely cut off from assistance, and face a growing risk of famine.

A spokesman for the Israeli military agency tasked with coordinating aid access in Gaza said in a briefing last month that there was “no starvation in Gaza. Period.” The agency, Cogat, has repeatedly said it does not limit the amount of humanitarian aid sent to Gaza.