At least 119 Palestinians, including 31 children, have been killed and more than 830 injured since the fighting broke out on Monday.
Hundreds of Palestinian families have fled to UN-run schools in northern Gaza to escape Israeli weapons.
Israeli artillery and tank shots fired in Gaza Thursday evening forced many families to flee their homes. Palestinians celebrated the first day of the religious holiday of Eid al-Fitr without a hitch in the air.
At least seven Israelis and one Indian citizen have also been killed. Israeli forces say hundreds of rockets were fired from Gaza into Israel.
Israel attacked more troops and tanks near Gaza and the Israeli security minister agreed to mobilize another 9,000 troops. But the military remained frustrated.