LES CAYES, Haiti, Aug 18 (Reuters) - A hungry crowd gathered outside an airport in southern Haiti on Wednesday as people left homeless by an earthquake that killed some 2,000 people voiced anger that government aid was slow to arrive five days after the disaster, leaving many without food and water. Prime Minister Ariel Henry, who flew to visit the worst-affected town of Les Cayes in southwest Haiti soon after Saturday"s quake of magnitude 7.2, had praised the dignity shown by survivors and promised a rapid escalation of aid. But following another night of rains, residents in Les Cayes, including those camped in a mushrooming tent city in the center of the town, complained of scant help on the ground. Dozens of people showed up at the local airport demanding food after a helicopter arrived carrying supplies, according to a Reuters witness. Police intervened to allow a truck carrying aid to leave. Pierre Cenel, a local judge in Les Cayes, a town of some 100,000 in habitants, aimed his ire at the government in Port-au-Prince, echoing the bubbling frustration in the hardest-hit regions. "As a judge, I must not have a political opinion. But as a man, as a man concerned about the situation of my country, nothing is working. They didn’t do anything to prepare for this disaster," Cenel said in downtown Les Cayes. Haiti, the poorest country in the Americas, is still recovering from a quake 11 years ago that killed more than 200,000. The latest calamity comes just over a month after the July 7 assassination of President Jovenel Moise plunged the country into political turmoil. Jerry Chandler, the head of Haiti"s Civil Protection Agency, which handles emergency response, said he was aware that aid had yet to reach many communities but said officials were working hard to deliver support and appealed for patience. "The frustration and despair of the population is understood, but ... the population is asked not to block the convoys so that the Civil Protection can do its job and help those in need," he told a news conference. There were at least 600,000 people in need of humanitarian assistance and 135,000 families displaced, Chandler said, adding that the goal was to deliver aid to everyone in need within a week. In an effort to avoid what it said was a confused response to the 2010 quake, Haiti"s government has sent a list of humanitarian needs to partners and is sorting the international aid as it arrives to distribute it to the most needy, Chandler said. On Wednesday morning, four U.S. Coast Guard helicopters landed in Les Cayes, bringing patients from more remote areas for treatment, according to an airport worker. The United States has dispatched humanitarian supplies as well as search and rescue teams to Haiti. Latin American countries such as Chile, Colombia, the Dominican Republic, Mexico, Panama and Venezuela have also sent food, medicine and supplies, and Taiwan - which has diplomatic relations with Haiti - also swiftly dispatched aid. Puerto Rican authorities said they were sending more rescue workers and doctors who were expected to arrive on Wednesday. RISK OF DISEASE In the fast-expanding tent city in Les Cayes, residents desperately pleaded for assistance. Aid workers have also warned about the risks of waterborne diseases, such as cholera. "We need help," said Roosevelt Milford, a pastor speaking on radio on behalf of the hundreds camping out in soggy fields since the quake destroyed their homes. Milford and others complained that they lacked even the most basic types of aid, such as food, clean drinking water, and shelter from the rain. Tanks of drinking water were destroyed during the quake, impacting reserves, authorities said. Tropical Storm Grace, which sloughed across southern Haiti this week, had swept away many shelters and inundated the field, adding to the misery. In a country with high levels of violent crime, residents had set up their own security teams to keep watch at night, paying particular attention to the safety of women and girls, he added. Security concerns about the gang-controlled areas on the route from the capital Port-au-Prince, as well as quake damage to some roads, have slowed access to some of the worst-affected zones difficult for aid and rescue teams. The U.N. Office for the Coordination of Humanitarian Affairs said on Tuesday that successful negotiations with armed groups had permitted a humanitarian convoy to reach Les Cayes. Chandler said the government was now escalating the number of aid convoys travelling by land, and hoped to soon reach three per day. However, he said flash flooding and landslides in the wake of Grace, which swept past Jamaica by Tuesday afternoon, worsened the difficulties of reaching remote communities. In the smaller town of L"Asile, some 60 km (40 miles) to the northeast of Les Cayes and home to more than 30,000 people, community leader Aldorf Hilaire said government help had yet to arrive, and survivors were reliant on support from charities such as Doctors Without Borders. "We are desperate," he told Reuters. "The springs are dirty: the water is not drinkable ... We had a bad night during the storm and the people need tents and tarps." HOSPITALS DAMAGED Authorities said on Wednesday that the earthquake had killed at least 1,941 people and injured some 9,900 others, but with rescuers still pulling bodies from the rubble the tally looks set to rise. In a rare piece of good news, 34 people had been rescued from under the rubble in the last two days, Chandler said, though as time passes, hopes for survivors dim. It was difficult to carry out search and rescue operations due to landslides in some areas, he added. Quake damage has hampered the work of several major hospitals. Doctors in makeshift tents have battled to save the injured, from young children to the elderly. Dozens in the Les Cayes tent city hailed from the nearby poor neighborhood of Impasse Filadelfia, where crumbling cement homes, contorted tin roofs and soaked mattresses lined narrow dirt roads. Water surged into the modest homes after a fast-moving river that edges the neighborhood burst its banks during the quake. "We are crying out for help," said one of them, Claudel Ledan. "All our houses collapsed and we need help from the government urgently." Reporting by Laura Gottesdiener in Les Cayes; Editing by Daniel Flynn, Clarence Fernandez, Philippa Fletcher and Marguerita Choy Our Standards: The Thomson Reuters Trust Principles.