Parts of northern Gaza are under Israeli siege and virtually no humanitarian aid has been delivered in 40 days, the UN warned earlier. Gazan medics say they are struggling to treat the injured, with aid agencies saying they cannot get essential supplies into the area. Israel's ground offensive in northern Gaza has displaced up to 130,000 people over the past five weeks. The UN says 75,000 people remain under siege with dwindling supplies of water and food in the towns of Beit Lahia, Jabalia and Beit Hanoun. Last week's report by Human Rights Watch said Israel had committed war crimes and crimes against humanity by deliberately causing the mass displacement of Palestinians in Gaza.