Palestinians walk in front of a building destroyed in an Israeli airstrike in Gaza City, Saturday, Jan.10, 2009

A top Hamas leader said Saturday the Gaza war has ended chances of negotiations with Israel and called on Arabs to pressure the Jewish State to end its attacks. Damascus-based Hamas leader Khaled Mashaal made his speech on the Arab news channel Al-Jazeera as Israel's military offensive in the Gaza Strip enters its third week.

Day 15 on Saturday - with more bombing, shelling and rocket fire.

Israeli war planes, helicopters and ships continued to shell targets in Gaza. Medical sources there reported one instance of at least eight Palestinians killed by an Israeli tank shell in the Jabalya refugee camp.

And, Israel is warning Gaza residents of more operations to come. The air force has dropped leaflets and the military has made random calls to people in Gaza with a general warning of further escalation.

Palestinian journalist Mohammed Dawwass is in central Gaza city and tells VOA he too received such a message. "The Israeli army called us last night saying they're going to continue on to Stage 3 (of the offensive) and they're warning us - you'd better be away from Hamas members, you should listen to the Israeli army orders and all this," he said.

Dawwass says such random calls are not uncommon and when they come people pass the message on to their families, friends and neighbors.

Gaza medical sources say the Palestinian death toll from the Israeli offensive is now over 800 and they estimate about half of these are civilians. Relief organizations have also warned of a deepening humanitarian crisis as hospitals struggle to cope with the wounded and food is increasingly hard to come by.

Mohammed Dawwass says daily life has become a struggle to survive with little food, no electricity, no reliable supply of water and the constant fear of bombing or shelling. "Life is becoming more difficult every day it passes.  Sometimes it's impossible to get anything.  The markets are closed. There is no life at all. If you're going to buy something you have to search, you have to smuggle to get it, you have to fight to get something to eat," he said.

Israel launched its offensive December 27 in retaliation, it said, to increased Hamas rocket attacks on southern Israel. The government says it will not stop until the rocket fire stops and Hamas is unable to re-arm.

Hamas continues to fire rockets into Israel.  Neither side seems ready to stop hostilities despite a UN resolution calling for an immediate cease-fire.  Talks are under way in Cairo, where Egypt is trying to broker a deal to end the fighting.