Tens of thousands of Palestinians have fled their homes, as Israel continued to press its offensive on the Gaza Strip.
Air strikes that struck the enclave on Wednesday killed at least 17 people, including four children, bringing the total deaths of Palestinians in the nine-day conflict to 213, with more than 1,450 wounded.
One Israeli was killed a day earlier by a Hamas-launched rocket, the only Israeli fatality since the fighting erupted on July 8.
The renewed bombardment on Wednesday destroyed several homes in Gaza, including the house of a senior Hamas official. The New York-based rights group Human Rights Watch called the destruction of civilian homes in the strip a war crime.
Israel on Wednesday morning told hundreds of thousands of residents of border areas to evacuate their neighbourhoods.
The warnings were delivered in automated phone calls, text messages and leaflets dropped from planes. Leaflets were also dropped threatening a new round of air strikes.
"We got leaflets and calls to evacuate," said Um Mohammed Rahmi, 56, who was fleeing in a donkey-drawn cart with six of her neighbours.
"We don't know where we are going. We don't know where we should go... We are just going aimlessly," she told Al Jazeera.
Hamas leaders targeted
The latest violence came a day after Israel initially accepted an Egyptian cease-fire proposal that called for a halt of hostilities. That was to be followed by talks on the terms of a longer-term cease-fire, including easing Gaza's seven-year-old border blockade by Israel and Egypt.
Hamas on Wednesday formally told Cairo it rejected the plan and instead launched more rockets at Israel.
As Cairo's effort collapsed, Israeli Prime Minister Benjamin Netanyahu warned that Hamas will pay a high price for rejecting the cease-fire plan.
The website of the Gaza Interior Ministry said Israel warplanes carried out dozens of air strikes before dawn Wednesday, targeting 30 houses, including those of senior Hamas leaders Mahmoud Zahar, Jamila Shanti, Fathi Hamas and Ismail Ashkar.
The Israeli army said the leaflets warned the residents of Beit Lahiya, Shaja'iya and Zeitoun to evacuate their homes "for their own safety".
It said a large numbers of rockets were launched from these areas and that Israel plans to bomb these locations.
"Whoever disregards these instructions and fails to evacuate immediately, endangers their own lives, as well as those of their families," the message said.
Nowhere to go
On Wednesday morning, hundreds of residents of the neighbourhoods of Zeitoun and Shijaiyah were seen walking in the streets, carrying small bags with belongings.
"We don't want to leave our homes, but we do this because of the children. There are many bombings and they get terrified." said the Um Ramez, as she and her grandchildren in Zeitoun packed the trunk of a car with clothes bags, a box of food and another box of tomato.
Um Ramez told Al Jazeera they were going to her son's home in the centre of Gaza city, which was "relatively safer".
The Wafa Rehabilitation Centre in Shijaiyah, which cares for 15 disabled and elderly patients, received several calls demanding the patients evacuate, said its director, Basman Ashi.
Ashi said an Israel shell hit near the building, causing damage to the second floor, but no injuries. He said he won't evacuate because his elderly patients have nowhere to go.