Armored Israeli forces attacked the Gaza Strip's main city from two directions on Monday and targeted the main road linking it to the south of Gaza, witnesses said, drawing more international appeals for Palestinian civilians to be protected.

Israel said its forces freed a soldier from Hamas captivity, one of 239 hostages Israel says were captured on Oct. 7 by Hamas gunmen from Gaza who rampaged through southern Israeli communities, killing over 1,400 people.

It identified her as Ori Megidish and said she had since undergone medical checks and is "doing well," the military said. It gave no details on the circumstances of her release.

Israel's military said it had struck more than 600 militant targets over the past few days as it expanded ground operations in the territory, where Palestinian civilians are in dire need of fuel, food and clean water as the war enters its fourth week.

Palestinian medical authorities in Gaza said on Monday that 8,306 people - including 3,457 minors - had been killed in Israel's three-week-old air and ground onslaught.

Significantly fewer humanitarian aid trucks have reached the besieged enclave than are required, say U.N. Officials, and civil order has broken down with people storming U.N. warehouses in search of food.

That has put four U.N. aid distribution centers and a storage facility out of action, the United Nations agency for Palestinian refugees (UNRWA) said on Monday.

"It's a disaster on top of a disaster. Health needs are soaring and our ability to meet those needs is rapidly declining," World Health Organization regional emergencies chief Rick Brennan told Reuters, reiterating international calls for a ceasefire to enable a larger humanitarian operation.

The White House said it was working to get more aid trucks into Gaza.