The International Committee of the Red Cross says people wounded in fighting in the Gaza Strip are dying because ambulances cannot reach them.
The ICRC says the situation is extremely dangerous because of the incessant attacks and military operations.
A spokeswoman said in Geneva on Monday that wounded people have died while waiting for Palestinian Red Crescent ambulances.
Some 555 Palestinians have now been killed and 2700 wounded since an Israeli offensive to halt Hamas rocket attacks began on 27 December.
The Red Cross says hospital emergency rooms and intensive care units are overwhelmed. At least two hospitals were out of fuel for their generators.
Water worries
The organisation is also concerned about water supplies: it says two of the 45 wells in the Gaza Strip are out of action and the pumps on eight others are no longer working because of power cuts.
It says half a million people, about one third of the population of the territory, could have no water.
