GAZA CITY AND CAIRO — Calls by Arab and European leaders for a cease-fire in the Gaza conflict intensified Tuesday in the aftermath of a mortar attack by Israeli forces on a United Nations school that killed at least 30 Palestinians who had sought shelter there.
Israeli officials, who said the school was targeted because Hamas militants had launched mortar rounds from its grounds, announced later in the day that they would establish a "humanitarian corridor" to transport vital supplies to Gaza Strip residents.
As raw video images of dead youngsters were beamed repeatedly throughout much of the globe, world political leaders reacted.
U.N. Secretary-General Ban Ki-moon opened a Security Council meeting saying, "Today's events underscore the dangers inherent in the continuation and escalation of this conflict. I call once again for an immediate cease-fire."
Palestinian Authority President Mahmoud Abbas, whose forces were ousted from Gaza in 2007 by Hamas, called the school deaths "a massacre" and urged intervention by the Security Council to protect Gazans from "genocide."
Meanwhile, Hamas continued to fire rockets at civilian targets in southern Israel, one striking a town less than 20 miles south of Tel Aviv.
A truce proposal from Egypt, which had mediated a six-month cease-fire between Israel and Hamas that collapsed last month, calls for both sides to stop fighting for a limited period to allow humanitarian aid to be shipped into Gaza. Egypt would then lead talks with the two sides to make long-term border arrangements and lift an Israeli blockade of Gaza.
At the Security Council, U.S. Secretary of State Condoleezza Rice discussed the Israeli humanitarian aid proposal but also pointed out the difficulty of distributing supplies. She said the U.S. would "actively work to relieve" any problems.
Israeli Ambassador Gabriela Shalev said her country was taking the Egyptian truce proposal "very seriously," but she also made it clear that Israel was not interested in any Security Council action that was not backed up by force on the ground. "Does anyone here truly believe that Hamas will heed the words of this council?" she asked.
In Gaza on Tuesday, as Israeli forces continued to pound deeper into urban neighborhoods, the street battles and bloodshed showed no signs of ebbing. Palestinian medical officials reported that 75 Gazans were killed as Israeli forces swept into more densely populated areas.
John Ging, the senior U.N. official in Gaza, said 30 Palestinians died and 50 were injured when three artillery shells sprayed shrapnel through the Al Fakhoura School in the Jabaliya refugee camp. Palestinian doctors put the death toll at 37, including women and children.
Hours before, the United Nations said another of its schools in the Shati refugee camp, also in northern Gaza, which had been closed because of the bloodshed, was hit by an Israeli missile early Tuesday, killing three Palestinian cousins who had taken shelter inside.
Hundreds of Gazans have been relying on U.N. buildings as havens amid the fighting between Israeli forces and Hamas militants that began 11 days ago when the Israelis initiated an air barrage designed to halt rocket attacks by Hamas on southern Israel.
The Israeli army said the school in Jabaliya was attacked after militants fired mortars from the campus. An army statement said Hamas "terror operatives" Imad Abu Askhar and Hassan Abu Askhar were among the dead.
"We face a very delicate situation where Hamas is using the citizens of Gaza as a protective vest," Israel Defense Forces spokesman Brig. Gen. Avi Benayahu said.
Fawzi Barhoum, a spokesman for the Islamic militant group, denied that his organization was staging attacks from the school and accused Israel of carrying out "an open war on innocent civilians."
Israeli warships battered the coast as troops and tanks, after intense fighting around Gaza City, pushed south to Khan Yunis, where skirmishes continued throughout the day.
Thousands of Gazan families have abandoned their homes, either to flee the front lines of the conflict or because of their proximity to police stations or security forces installations. Those who don't seek safety in public shelters, such as the U.N.-run schools, often shuffle between the homes of relatives.
But even many purely civilian neighborhoods aren't safe because Gaza militants often fire rockets from such areas and Israel continues to bomb the homes of Hamas commanders and buildings and mosques it believes are used as weapons storehouses. As a result, almost every neighborhood in Gaza is littered with sites that Israel considers legitimate military targets.
The situation is perilous even for those seeking maternity care in Gaza's overloaded hospitals. Pregnant women face the decision of whether to deliver at home or risk trying to reach a medical facility, where critically injured patients take priority. Gaza City's main Shifa Hospital emptied its maternity ward on the first day of the Israeli air assault.