Rescuers have been digging by hand in the frantic search for survivors in the Indonesian city of Palu, which is reeling from an earthquake and tsunami.
At least 408 people have been killed but there are fears the death toll could rise significantly as workers reach areas closer to the epicentre.
Search efforts are being hampered by blocked roads and a collapsed bridge.
The Red Cross estimates that more than 1.6 million people have been affected by the earthquake and tsunami.
There are particular concerns about the town of Donggala, where the impact is still unclear.
"This is already a tragedy, but it could get much worse," the Red Cross said in a statement.
Yenni Suryani, the Indonesia country manager for the aid agency Catholic Relief Services, said Donggala appears to be inaccessible by road or air and that help may have to come by sea.
Strong aftershocks have continued to hit the island since Friday's earthquake.
Rescue teams dug by hand to free 24 people trapped in the rubble of the Roa-Roa hotel in the city of Palu.
The hotel's owner told local media people could still be heard crying out for help, but said that no heavy lifting equipment was available to rescue them.
Dozens remain missing in the city of 335,000, some thought to be trapped in the debris of collapsed buildings.
سایت تابناک از انتشار نظرات حاوی توهین و افترا و نوشته شده با حروف لاتین (فینگیلیش) معذور است.