Palestinians began leaving northern Gaza on Friday after Israel’s military told about 1 million people to evacuate to the south of the besieged territory ahead of an expected ground invasion in response to Hamas"s attack on Israel last Saturday. The ruling militant group told residents to ignore the evacuation order. The UN said ordering almost half the Gaza population to leave en masse would be calamitous, and it urged Israel to reverse the unprecedented directive. In the week-old war, the Gaza health ministry said on Friday that roughly 1,800 people have been killed in the territory – more than half of them under the age of 18 or women. The assault by Hamas killed more than 1,300 Israelis, most of whom were civilians, and roughly 1,500 Hamas militants were killed during the fighting, the Israeli government said