GAZA CITY (AFP) - The shelling is incessant, hospitals are overwhelmed, children are shell-shocked, the Gaza nights are miserably cold in the windowless homes. And residents fear their nightmare could worsen. After days of intense bombardment from the air, artillery shells are now pounding the Gaza Strip as the fighters return fire with rocket-propelled grenades at Israeli tanks. Children, who make up more than half of the 1.5 million population, are traumatised, living in fear of the next explosion that will shake their home. "Many kids have stopped eating. They are inactive, they barely talk, they cling to their parents all the time," said Sajy Elmaghinni, who works for the UN Children's Fund (UNICEF) in Gaza. "Children are now scared of the dark, which is a major problem because there's no electricity," says Elmaghinni, whose own home has been without power for five days. He has no way of heating his home where all the windows were blown out by a blast, but like others in the besieged Palestinian enclave he has become used to dealing with the cold. "We just wear a lot of clothes." But with most homes and hospitals lacking heating and with temperatures near freezing, the risk of hypothermia, is particularly high for newborn babies who need higher temperatures to survive, Save the Children said. The humanitarian group said that even before the Israeli offensive, around 50,000 children were suffering from malnutrition in Gaza, which has been under a crippling Israeli blockade for 18 months. For Elmaghinni a key concern is how he'll get his nine-month pregnant wife to the hospital when she is due to deliver. "This is a major concern. At the beginning of the bombing she experienced some trauma when a neighbouring building was hit. "Everybody evacuated our building. We had to stay. I didn't know what to do. I prayed to God my wife would not deliver in these conditions. A number of pregnant women have moved in with friends or relatives who live near a clinic, so as to have a doctor nearby, aware that ambulances are busy collecting the victims of the Israeli attacks. At night it is impossible even to walk to a clinic, "because drones pick up anything that moves," says Elmaghinni. Some of the missiles fired on Gaza are launched from unmanned aircraft that can be heard flying overhead. Virtually everyone has a tragic story to tell in this shell-shocked coastal strip already crippled by the Israeli blockade. Hospitals are completely overwhelmed. They used to have five surgeons to operate on a severely wounded patient. Now a surgeon might have to operate on as many as 10 patients in a day, doctors said. Amputations are increasingly frequent as doctors do not have time to try to save limbs. Many wounded people have died because they could not be treated in time, according to health authorities. In Gaza City the nightmare is compounded by uncertainty as Israel's troops move closer. "The scariest part is not knowing when they will move into the city. When they do, there could be many civilians killed," says Elmaghinni. Residents live in fear, and the streets of the city are deserted. In any case there's nowhere to go. Supermarkets are virtually empty. There is no cooking gas and UN food aid distribution has been suspended. When civilians do venture out into the streets it is usually to move to slightly safer locations, from high-rise buildings that rattle when there's a blast or from homes too close to potential targets " mosques, government offices or the homes of Hamas officials.