More than 400 people were confirmed killed, many swept away as tsunami waves triggered by a massive earthquake crashed into the Indonesian island of Sulawesi, and authorities expected the toll to rise sharply on Sunday as news arrives from remote areas.
The tsunami struck after a warning was lifted because the nearest tidal sensor was 300 kilometres south of the city of Palu and only detected an “insignificant” six-centimetre wave.
Waves were initially reported as two metres high, later raised to three metres, but the funnel effect of the shape of Palu harbour meant some waves were up to six metres.
The Head of the National Disaster Management Agency (BNPB), Willem Rampangilei, told reporters in Sulawesi late on Saturday that the death toll from Palu had reached 420 people, according to news website Kompas.
Indonesia’s Vice President Jusuf Kalla warned it could rise into the thousands.
Mr Kalla issued the warning on Saturday afternoon local time, pointing out there was “no word” yet from a city of 300,000 people.
Echoing the concern, the Red Cross said the lack of communication with the city of Donggala was “extremely worrying”.
“We’re now getting limited communications about the destruction in Palu city, but we have heard nothing from Donggala and this is extremely worrying,” a statement from the organisation said.
More than 600,000 people live in Donggala and Palu.
The Red Cross said its staff and volunteers were heading to the affected areas.
Indonesian disaster agency spokesman Sutopo Purwo Nugroho said 384 people had been killed in the hard-hit city of Palu alone, and communications “were totally crippled with no information” from Donggala.
He said the fate of “tens to hundreds” of people who were taking part in a beach festival in Palu when the tsunami struck at dusk on Friday was also unknown.
“When the (tsunami) threat arose yesterday, people were still doing their activities on the beach and did not immediately run and they became victims,” said Mr Nugroho.
“The tsunami didn’t come by itself, it dragged cars, logs, houses, it hit everything on land,” he said, adding that the tsunami had travelled across the open sea at speeds of 800 kilometres per hour before striking the shoreline.
Some people climbed trees to escape the tsunami and survived, he said.
Amateur footage shown by local TV stations showed waves crashing into houses along Palu’s shoreline, scattering shipping containers and flooding into a mosque in the city.
Photos confirmed by authorities showed bodies being lined up along the street on Saturday, some in bags and some with their faces covered with clothes. Around 16,700 people were evacuated to 24 centres in Palu.
Aerial photographs released by the disaster agency showed many buildings and shops destroyed, bridges twisted and collapsed and a mosque surrounded by water.
Tsunami expert Abdul Muhari, who heads a tsunami research team within the Indonesian government, told ABC the death toll for the Palu Bay area would likely top 1,000 based on figures he received on Saturday evening from the head of the search and rescue team.
“If we assume they have just worked in 20 per cent of the search and rescue area and already have confirmed almost 400 casualties, then we could expect a figure probably higher than 1,000,” he said.