Israeli Forces Move Into Gaza

"The residents of Gaza are not the target of the operation," the statement added. "Those who use civilians, the elderly, women and children as 'human shields' are responsible for any and all injury to the civilian population. Anyone who hides a terrorist or weapons in his house is considered a terrorist."

An Israeli army mobile artillery piece fires towards targets in the southern Gaza Strip, on the...

An Israeli army mobile artillery piece fires towards targets in the southern Gaza Strip, on the Israel side of the border with Gaza, Saturday, Jan. 3, 2009. Israeli warplanes, gunboats and artillery units blasted more than 40 dozen Hamas targets Saturday, including weapons storage facilities, training centers and leaders' homes, before launching a ground invasion of Gaza.

(Sebastian Scheiner/AP Photo )
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Mosque Hit

Earlier Saturday, at least 10 people were killed in an Israeli air strike on a mosque in northern Gaza, Palestinian medical officials told the Associated Press.

It was not immediately clear whether those killed in the mosque attack in the northern town of Beit Lahiya were militants or civilians.

In a separate attack, the Israeli army claims to have killed Abu Zakaria al-Jamal, the latest senior Hamas leader to have perished since the attacks began eight days ago.

According to the United Nations, Israeli forces have hit 600 targets since the air strikes began.

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The beginning of artillery attacks Saturday before the ground invasion raised the possibility of additional civilian casualties caused by the relative inaccuracy of artillery shells compared with precision missile strikes, according to an AP report.

'No Place to Hide'

Before the ground attack, Israel allowed some 300 Palestinians who hold dual citizenship to leave the heavily bombed region of over 1 million residents Friday after pleas from other governments that they be permitted to leave.

"There is no place to hide," Palestinian-American Jawahir Haggi told ABC News. "You want to go to a house, do you want to go and hide? You find bombs and the Israelians [sic]. You go to another house, you find bomb and Israelians [sic]. There is no place to hide."

According to U.N. reports, some aid is getting through, but not enough to cope with the massive demands the conflict has placed on food resources, hospitals and utilities.

Many civilians have not survived long enough to feel the aid shortage.

The U.N. estimated Friday that a quarter of the Palestinians killed in air strikes were civilians.

"They are supposed to destroy just the Hamas, but people in their homes are dying too," Hajji, a 14-year-old U.S. citizen, told the AP.