Israel has further intensified its attacks on Gaza, warning its war on Hamas would be “long and difficult”, as calls mounted to end the violence and the Red Cross warned of “intolerable” suffering.

AFP said thousands of buildings have been flattened in the overcrowded territory of 2.4 million people, with more than half the population displaced as Israel imposed a near-total siege.

Mirjana Spoljaric, president of the International Committee of the Red Cross, voiced shock at the “intolerable level of human suffering”, urging all sides to de-escalate the conflict.

Hamas authorities have reported a “large number” of people killed overnight in strikes on two refugee camps in northern Gaza.