Casualties have been pouring into over-stretched hospitals in the Gaza Strip as Israel presses on with its offensive against Palestinian militant groups.
Palestinian medical officials say at least 90 people, including many civilians and 26 children, have been killed since the ground assault began.
'Mainly civilians'
There were reports of fierce fighting in northern Gaza as news began to emerge of the scale of the problems facing medical staff.
Norwegian doctor Mads Gilbert, one of two foreign doctors working at Gaza's biggest hospital, al-Shifa, said they had received a "new wave" of very serious injuries on Monday.
"We have many amputations, head injuries, and of course for a hospital in this situation... it's extremely difficult to handle," he told the BBC.
He warned that the hospital would be unable to operate much longer unless it received fresh medical supplies.
"People are dying now because of lack of supplies. We have all operating rooms full. Yesterday we were operating on two patients in one operating room... This is a complete disaster".
But Dr Gilbert said the overwhelming majority of casualties he had treated were civilians.
"Among all the hundreds we have seen so far, we have seen two fighters," he said, adding that women and children alone made up 25% of the death toll, and 45% of the wounded.
Humanitarian crisis
For the people of Gaza, living conditions are deteriorating sharply. Supplies of fuel, food, water, and wheat are said to be running desperately low.
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A spokesman for Unrwa, the UN aid agency for the Palestinians, said food was urgently needed and people were facing "serious hunger", with supplies for just 48 hours.
"One million people are without electricity. Crucially the hospitals in Gaza are running on emergency generators. This in my book amounts to a humanitarian crisis," Christopher Gunness told the BBC.
BBC NEWS | Middle East | Casualties rise in Gaza offensive