Benjamin Netanyahu has said that Israel is prepared for a "significant expansion" of the ground invasion in Gaza, after overnight bombardments killed dozens of Palestinians.
The Israeli prime minister said on Friday he had instructed the army to "prepare for the possibility of significantly widening the ground operation".
"We don't want to kill civilians, but Hamas is a terrorist organisation that hides behind human sheilds," Netanyahu said.
He said the ground invasion's stated aim of destroying tunnels used by Hamas fighters could not be done "only from the air".
His comments came after a night of bombing throughout the Hamas-ruled Palestinian territory, which killed 24 Palestinians and injured a further 200.
The Israeli army announced that a soldier had been killed and two others were wounded in operations inside Gaza.
The overall death toll has risen to at least 285 Palestinians since the beginning of Israel's operation eleven days ago.
Israeli troops had moved several kilometres into the territory in operations the army said were targeting tunnels used by Hamas but the incursions so far appeared limited.
Gaza City resident Ebaa Rezeq told Al Jazeera that while Israeli soldiers remained near the buffer zone, air raids and shelling were continuing to terrify civilians.
In one of the air raids, a building housing local media offices in Gaza City was struck by three bombs. Israel maintains that the offensive is to destabilise Hamas and "demilitarise" Gaza.
Al Jazeera's Nicole Johnston, reporting from Gaza, said that the attack was "just a small example of what's been happening here across Gaza Strip all night".
Al Jazeera's Stefanie Dekker, also in Gaza, said Israeli troops were targeting the tunnels which Palestinian fighters were using.
"Hamas has managed to set up a tunnel - the Gaza under Gaza - which is a new thing that didn't exist in the last conflict," she said.
On Thursday morning, a group of attackers had tried to enter southern Israel through a tunnel from Gaza. The Israeli army said eight of the 13 men were killed.
The Qassam Brigades, the armed wing of Hamas, said it carried out the raid.