PORT-AU-PRINCE (AFP/Reuters) - Despairing Haitians clawed by hand to seek survivors in the rubble of their homes as frustration grew at the trickle of aid Friday after a quake the Red Cross said may have killed 50,000 people. A stench of death hung over the capital Port-au-Prince with rotting bodies littering the streets as residents spent a third night in the open, rattled by aftershocks following Tuesdays 7.0 earthquake. Despite the launch of a massive global aid operation, there was no sign of heavy lifting equipment among the ruins as tons of material and badly needed supplies clogged up the international airport. Adding to the logistical nightmare were reports of looting and gunshots in the scramble for help, forcing some rescue crews to stop work at nightfall. If international aid doesnt come, the situation will deteriorate quickly. We need water and food urgently, said one survivor, Lucille. Some 7,000 dead had already been buried by Thursday, Perus Prime Minister Velasquez Quesquen said from Port-au-Prince, after Haitian officials earlier warned the overall toll might exceed 100,000. The United Nations said three million people lived in areas hit hardest by the quake and that 300,000 had been left homeless. The International Committee of the Red Cross said the quake, the largest to hit the Caribbean country in more than 150 years, had killed 40,000 to 50,000 people. We have lost everything. We are waiting for death. We have nothing to eat, nowhere to live. We have had no help. No one has come to see us, said quake victim Andres Rosario, speaking at an improvised camp set up by survivors at a rubbish dump in Port-au-Prince. No one is helping us. Please bring us water or people will die soon, said another resident Renelde Lamarque, who has opened his home yard to about 500 quake victims in the devastated Fort National neighbourhood. Raggedly-dressed survivors held out their arms to foreign reporters in the streets, begging for food and water. Amid fears that local anger and frustration over delays in receiving help could explode into violence, US Defence Secretary Robert Gates said that aside from some scavenging for supplies and minor looting the security situation on the ground in Haiti remained pretty good. The key is to get the food and the water in there as quickly as possible so that people dont in their desperation turn to violence or lead to the security situation deteriorating, Gates told reporters in Washington. The United States is leading a massive international relief effort. Relief workers said some aid was trickling through to people but in haphazard fashion. Some aid is slowly getting through, but not to many people, said Margaret Aguirre, a senior official with International Medical Corps. I havent eaten since the day before yesterday, said Bertilie Francis, 43, who was with her three children. We are here by the Grace of God, nobody else, she said. Health experts say that while dead bodies smell unpleasant, in cases where people have been killed in traumatic accidents and not by contagious diseases such as cholera there is little health risk from even large numbers of decomposing corpses. UN aid agencies were to launch an emergency appeal for approximately $550 million on Friday to help survivors. UN Secretary-General Ban Ki-moon said he planned to go to Haiti very soon In the capital overnight, an eerie chorus of hymns, prayers, groans and wails of mourning, mixed with the barking of terrified dogs, echoed over the hilly neighbourhoods. Little aid had trickled down to the streets. An AFP video showed scuffles breaking out as a helicopter dropped food over one part of Port-au-Prince. Sporadic gunshots could be heard, and witnesses said there had already been some looting in a city sadly familiar with bloodshed and natural disasters. Our biggest problem is insecurity. Yesterday they tried to hijack some of our trucks. Today we were barely able to work in some places because of that, said Delfin Antonio Rodriguez, rescue commander for the Dominican Republic. In the agonising wait, residents dug through mountains of concrete, their efforts punctuated by the screams and moans of those trapped. Some set up temporary shelters with sheets and covers; others trekked out carrying meagre belongings, searching for refuge outside the city. Doctors struggled to treat the vast numbers of sick and injured. Hundreds of corpses, some mutilated and half-clothed, lay rotting outside the flattened central hospital, waves of distraught Haitians moving from body to body in search of loved ones. Haitian-born rap star Wyclef Jean called it the apocalypse. We spent the day picking up dead bodies, all day thats what we did, he told Fox News. Theres so much bodies in the streets that the morgues are filled up, the cemeteries are filled up. Dozens of people were rescued as sniffer dogs began to comb the ruins, but moments of joy were few. The international community has so far pledged some 268.5 million dollars in aid, according to the UN. Governments promised money, experts and equipment, donations rolled in by text message and Internet and Hollywood idols lent their star power to appeals for funds. China, France, Iceland, the United States and Venezuela were among nations with teams on the ground. The aid coming in includes field hospitals, doctors, medicines, search and rescue teams with sniffer dogs, water and water purification equipment, food, tents, blankets, heavy-lifting equipment as well as soldiers and experts. The USS Carl Vinson, a giant nuclear-powered aircraft carrier, was due to drop anchor off the stricken nation later Friday. The carriers cavernous space, ordinarily reserved for fighter planes, is now filled with 19 helicopters to dispatch water, medicine and other aid. Obama and French President Nicolas Sarkozy, along with Brazil, Canada and others, will hold a conference on reconstruction, the French presidency said.