Smoke from Israeli operations rises near Gaza City, 6 Jan 2009

Medical officials in Gaza say dozens of Palestinians were killed in Israeli attacks Tuesday, including at least 30 in one attack when Israeli troops fired on a U.N. school. The Israeli military offensive is now in its second week and it is estimated the Palestinian death toll is more than 600. Israel says it has agreed to set up a "humanitarian corridor" to allow residents of the Gaza Strip to stock up on vital goods and prevent what it calls a humanitarian crisis during the military offensive against Hamas militants.

It was day 11 of the Israeli military offensive in Gaza. Israeli war planes, tanks and artillery struck at targets throughout the densely populated strip of land and in several instances hit U.N. run schools.

A Palestinian woman reacts outside Shifa hospital in Gaza City, 06 Jan 2009

Local medics say artillery or tank shells hit a school in the Jabiliya refugee camp.

John Ging from the U.N. Relief and Works Agency in Gaza said the school was clearly marked as a U.N. compound. "The school in Jebaliya is a preparatory girls' school in normal circumstances. Again, very visible, clearly marked building - as all of our buildings are. And as I said already, we provided the GPS coordinates to the Israeli military and updated regularly with them and this year again, so they are fully familiar with where our locations are, and again, flag flying there," he said.

Several hundred people had taken shelter in the school to try to escape the Israeli attacks. Israeli military officials say they believe militants were using the school to fire upon Israeli troops. U.N. officials say thousands of Palestinians have been seeking shelter in schools throughout Gaza from the ongoing shelling, air strikes and bombardments.

In Gaza, international Red Cross spokesman Iyad Nasr says the situation is dire. "The situation is becoming unbearable and more casualties are being seen among the population, the civilian population, including paramedics, including hospitals and ambulances," he said.

But, there is no indication Israel is ready to call off its campaign, despite growing international pressure to do so.

Israeli leaders say their offensive is aimed at stopping Hamas rocket attacks on southern Israel. Hamas military leaders say they will fight the Israeli forces in every street, alley and house.