Indonesian authorities on Tuesday raised the death toll to 1,234 in the 7.5-magnitude earthquake and subsequent tsunami that hit Sulawesi island last week.
The twin disasters on Friday left the coastal city of Palu and the adjoining areas in ruins.
Tens of thousands of people were growing increasingly desperate for food, fuel and water.
According to Indonesia’s National Disaster Management Agency, hundreds of people may still be trapped under the rubble of buildings.
Rescue teams were still not able to reach all the affected areas.
There were reports of officers firing warning shots and tear gas to ward off people ransacking shops in Palu, a coastal city ravaged by a 7.5-magnitude quake and the tsunami it spawned.
Almost 200,000 people are in need of urgent help, the United Nations says, among them thousands of children.
Police said Tuesday that they had previously tolerated desperate survivors taking food and water from closed shops, but had now arrested 35 people for stealing computers and cash.
"On the first and second day clearly no shops were open. People were hungry.
"There were people in dire need. That’s not a problem," said deputy national police chief Ari Dono Sukmanto.
"But after day two, the food supply started to come in, it only needed to be distributed. We are now re-enforcing the law." "There are ATMs. They are open," he added.
Despite official assurances, desperation was evident on the streets of Palu, where survivors clambered through wreckage hunting for anything salvageable.
Others crowded around daisy-chained power strips at the few buildings that still have electricity, or queued for water, cash or petrol being brought in via armed police convoy.
"The government, the president have come here, but what we really need is food and water," Burhanuddin Aid Masse, 48, told AFP.
The Indonesian military is leading the rescue effort, but following a reluctant acceptance of help by President Joko Widodo, international NGOs also have teams on the ground in Palu.
With the ground still shaking from aftershocks, people were still too afraid to go indoors.
An earthquake measuring 6 on the Richter scale rocked Sumba island of Indonesia on Tuesday, but there were no reports of any damage.
Colonel Muhammad Thohir of the Indonesian Army said that authorities need to send aid via helicopter in areas like Donggala, one of the towns most affected by the tsunami, as well as other districts which were not accessible to the rescuers.
He said gasoline and water supplies were being transported to the Sulawesi island, but they were still insufficient for the people affected.
Indonesian officials said that priorities included sending food to those in need, conducting a mass burial of victims, and guaranteeing the security of the airport, which was expected to start receiving commercial flights on Wednesday.>