Claims have been received by the BBC and an Israeli human rights group that Israeli troops have fired on Gaza residents trying to escape the conflict area. Israel has strongly denied the allegations.
BBC journalists in Gaza and Israel have compiled detailed accounts of the claims.Some Palestinian civilians in Gaza say Israeli forces shot at them as they tried to leave their homes - in some cases bearing white flags.
One testimony heard by the BBC and human rights group B'tselem describes Israeli forces shooting a woman in the head after she stepped out of her house carrying a piece of white cloth, in response to an Israeli loudhailer announcement.
The BBC also spoke to Marwan Abu Rida, a paramedic with the Palestinian Red Crescent, who says he was called to the site at 0810 local time (0610 GMT).
But he says he came under fire as he tried to reach it, and was trapped in a house nearby until 2000 (1800 GMT) because of Israeli shooting.
He said that when he reached the location he found the dead woman, Rawhiya, who appeared to have been shot in the head, as well as the younger woman who was injured.
The Israeli military has dismissed the report as "without foundation".
The BBC has spoken to members of another family who say they are trapped in their home by fighting and have been shot at when they tried to leave to replenish dwindling water and food supplies, even during the three-hour humanitarian lull.
Israel is denying access to Gaza for international journalists and human rights monitors, so it is not possible to verify the accounts.
B'tselem said it had been unable to corroborate the testimony it had received, but felt it should be made public.
"When we were walking, with the women first, they saw soldiers and they started to shout to them, to tell them 'we have children, we have children'. They started to shoot us. My aunt was killed with a bullet in her head." Riad Zaki al-Najar, gave the BBC an account by telephone.