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. Authorities said 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, the BBC reported.

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.

So far, 153 victims have been buried in mass graves to prevent an outbreak of disease caused by decomposing bodies. According to a CCN report, more than 100 corpses were still lying in the yard outside the Undata Hospital in Palu. 

The hospital's director, Komang Hadi Sujendra, said the one facility alone had received over 200 bodies since the tsunami.

An estimated 2.4 million people were affected by the disaster, said the disaster management agency spokesman Sutopo Purwo Nugroho. He said that 800 were badly injured and more than 61,000 people were displaced.