After a powerful earthquake triggered a tsunami and soil liquefaction on the Indonesian island of Sulawesi, search teams continue to find bodies as traumatised survivors recount the moment disaster struck.

The death toll from the 7.5-magnitude quake now officially stands at 1,649, but there are fears on the ground the true figure could be several thousand higher.

A search team continues to work its way slowly through the rubble in the village of Balaroa at the weekend, as resident Agus Rivani perseveres with his own desperate search for the bodies of his wife and daughter.

Indonesia tsunami: aid finally arrives, but hopes of finding survivors fade Read more

“See those bubbles on the surface over there,” he said, gesturing to a black pool of water. “I think that could be coming from them.”

Agus’s hands shake as he pulls out his mobile phone to look at their last family photo. Taken a few months ago, it shows the family around the kitchen table, his 12-year-old daughter Nurul Hisan smiling broadly in the foreground, and behind Agus and his wife, Stella Djumaan, in a mustard hijab.

Facebook Twitter Pinterest Balaroa residents carry belongings salvaged from their collapsed homes. Photograph: Aaron Favila/AP

He and his neighbours had brought in a petrol-powered water pump, and were squatting around the edge of the swampy pool preparing to start draining it to see if his theory was correct.

When the earthquake hit a few minutes after 6pm last Friday, Agus had called out to his wife and daughter, telling them to stay inside. That was the last time he saw them.

As the ground oscillated wildly, tiles began to crack, his house started to slide and a wall collapsed. Agus sought refuge under the kitchen table. When he emerged, he found his 10-year-old son Fathan had survived, a blessing in a week that for so many has ended in bewilderment and grief.

Indonesia quake: bodies sent straight to graves as Palu prioritises survivors Read more

The destruction in Balaroa, a village in the hills around the city of Palu that overlooks its picturesque bay, defies comprehension. The quake broke up roads as if they had been made of porcelain, creating asphalt chasms and hills metres high out of what was once level ground.

Balaroa is a kaleidoscope of disaster made up of rubble, rusty corrugated roofs, bricks and timbers, dotted with random personal belongings – a single shoe, teddy bear, or wedding invitation embedded in the mud.

On the coast it was the tsunami rather than the quake that did most damage, flattening swathes of coastline. In Petobo it was liquefaction, a process where shaken soil is saturated with water, turning it into deadly quicksand.

Play Video 0:52 Swamped by mud: drone footage of Indonesia’s Petobo village – video

The land on which Balaroa was built made it particularly vulnerable to the quake. “Balaroa was a swamp in the forest originally,” explained Cahyo Nugroho, a seismologist from Indonesia’s meteorology and geophysics agency stationed in Palu. “So the land was not stable.”

Abdul Maruf, 40, was just stepping out of his house to join Friday evening prayers when he felt it. “Earthquake, get out!” he shouted to his wife and young children. “We got out and then the house crumbled to the ground about 15 seconds later.”

“I keep having flashbacks,” says his wife, Aviah, as she rocks her baby to sleep. “Every step I took the land broke off, split off. I was shocked.”

In the immediate aftermath, people in Balaroa’s Manggis Road streamed out of their houses in panic. A video shot by Aviah’s younger brother Rizal showed panicked residents surveying the damage in the dusk light.

When the quake struck, Rizal did not think it would be so bad, particularly because there had been several weaker tremors earlier in the afternoon. “I’m so glad everyone in my family is safe,” he said. “So many others lost people, their husbands or wives or children. I am so thankful.”

Facebook Twitter Pinterest Women console each other after identifying the body of a relative in Balaroa village. Photograph: Athit Perawongmetha/Reuters

The logistics of responding to the disaster have been fraught with difficulty. Indonesia is an archipelago of more than 13,000 islands spread over more than 3,000 miles, and Sulawesi is in the country’s more remote east. The damage to Palu’s airport limited capacity to get supplies to where they were needed most.

Aid is now arriving, from Jakarta, neighbouring Borneo, Australia, Japan and the UK, but there were still reports of desperate residents in outskirt areas such as Sigi raiding passing cars for petrol and supplies. In Donggala earlier in the week, residents held out cardboard boxes to passing cars, placing planks of wood and rope across the road to force them to slow down.

'I never believed there could be a tsunami': Palu tells of survival and loss Read more

In Palu, home to 300,000 people, some signs of normality are returning, but for some residents, such as Yaser Garibald, Palu will never be the same.

Yaser rushed to Balaroa on Friday night to search for his 60-year-old mother, Masri. He was unable to find her until the first light of dawn when he heard a faint voice coming from the rubble. She was wedged between two blocks of concrete with her arms wrapped around his nephew, Ririn, 23.

“It hurts. It’s hard to breathe,” Masri told her son, as he hammered at the concrete in an attempt to free. In her last moments he was able to pass her water, but he was unable to save them.

Asked what kind of person she was, Yaser said he would remember his mother’s final selfless act. When the earthquake struck she had made it out but then went back for her grandson. “We dug her out and carried her away in a sarong,” he said.