"I'm so happy," said Heruwanto, 63, who goes by one name. He was clutching a box of instant noodles. "I really haven't eaten for three days."
Food, water, fuel and medicine had yet to reach the hardest-hit areas outside Palu, the largest city heavily damaged in Friday's disasters. Many roads were broken and split by the violent shaking or are blocked by debris and communications lines are down in the damage zone.
"We feel like we are stepchildren here because all the help is going to Palu," said Mohamad Taufik, 38, from the town of Donggala, where five of his relatives are still missing. "There are many young children here who are hungry and sick, but there is no milk or medicine."
The official death toll is 1,234 and hundreds were injured, but officials acknowledge scores of uncounted bodies could still be buried in collapsed buildings in Sigi and Balaroa.
The U.N. humanitarian office said "needs are vast," with people urgently requiring shelter, clean water, food, fuel and emergency medical care.
Water is the main issue because most of the supply infrastructure has been damaged, U.N. deputy spokesman Farhan Haq told reporters at U.N. headquarters in New York.
More than 25 countries offered assistance after Indonesian President Joko "Jokowi" Widodo appealed for international help. Little of that, however, has reached the disaster zone, and increasingly desperate residents grabbed food and fuel from damaged stores and begged for help.
Haq said the government is coordinating emergency efforts, and U.N. and relief agencies are on the ground or en route. He said the agencies are working closely with the government to provide technical support.
An aircraft carrying 12,000 liters (3,170 gallons) of fuel had arrived, and trucks with food were on the way with police escorts to guard against looters. Many gas stations were inoperable either because of quake damage or from people stealing fuel, national disaster agency spokesman Sutopo Purwo Nugroho said in Jakarta.
The frustration of waiting for days without help has angered some survivors.
"Pay attention to Donggala, Mr. Jokowi. Pay attention to Donggala," yelled one resident in a video broadcast on local TV, referring to the president. "There are still a lot of unattended villages here."
The town's administrative head, Kasman Lassa, all but gave residents permission to take food — but nothing else — from stores.
"Everyone is hungry and they want to eat after several days of not eating," Lassa said on local TV. "We have anticipated it by providing food, rice, but it was not enough. There are many people here. So, on this issue, we cannot pressure them to hold much longer."
Nearly 62,000 people have been displaced from their homes, Nugroho said.
More aid was being distributed, but "we still need more time to take care of all the problems," Nugroho said.
Teams continued searching for survivors under destroyed homes and buildings.
Many people were believed trapped under shattered houses in the Palu neighborhood of Balaroa, where the earthquake caused the ground to heave up and down violently.
"I and about 50 other people in Balaroa were able to save ourselves by riding on a mound of soil which was getting higher and higher," resident Siti Hajat told MetroTV, adding that her house was destroyed.
A handful of disaster personnel arrived in the neighborhood Tuesday morning. A lone backhoe cleared a path into the jumble of twisted buildings.
Sa'Adon Lawira, who lost a grandchild, was angry that rescue efforts focused so quickly on places such as the Palu hotel where tourists were staying.
"Why did the search-and-rescue agency and others prioritize the search for victims in hotels?" he said, holding back tears as he spoke. "Neighborhoods like this should take precedence because the bodies of residents are buried, but there are no rescuers who have searched for them."
Near the coast, the tsunami shattered buildings, uprooted concrete and thrust boats inland. The deadly wave reportedly reached as high as 6 meters (nearly 20 feet) in places.
In Palu's Petobo neighborhood, the quake caused loose soil to liquefy, creating quicksand-like mud that caused massive damage. Hundreds of victims are still believed to be buried in the mud there.
Liquefaction is a known phenomenon of earthquakes and can be compared to walking on a sandy beach.
"If you walk across some wet sand a little back from the water's edge, it is usually firm walking, even though you might leave footprints," said Adam Switzer, an expert at the Earth Observatory of Singapore. "However, if you stand still and wiggle your toes and feet, you will probably sink a little as the sand around your feet becomes soft and unstable. This is similar to what happens during liquefaction."
Australia announced it will send 50 medical professionals as part of a $3.6 million aid package. The United States and China are among other countries that have offered assistance.
The U.N.'s Haq said the Indonesian Ministry of Social Affairs has asked the U.N. children's agency, UNICEF, to send social workers to the affected area to support children who are alone or became separated from their families. And he said the World Health Organization is warning that a lack of shelter and damaged water sanitation facilities could lead to outbreaks of communicable diseases.
Indonesia, a vast archipelago of 260 million people, is frequently struck by earthquakes, volcanic eruptions and tsunamis because of its location on the "Ring of Fire," an arc of volcanoes and fault lines in the Pacific Basin. A powerful quake on the island of Lombok killed 505 people in August.