At least 520 people are now known to have died in a powerful quake that struck the Indonesian island of Sumatra on Wednesday, according to the government.
Rescuers struggled in heavy rain on Thursday to find survivors in the rubble of collapsed buildings. More than 400 people have been seriously injured, and the death toll is expected to rise, officials say.
The 7.6 magnitude quake struck close to the city of Padang, the capital of West Sumatra province, at 5.16pm local time. It brought down hundreds of buildings, including hospitals, cut power lines and triggered landslides, the BBC reports.
The social affairs ministry gave the latest confirmed death toll of 529, but Rustam Pakaya, head of the health ministry's disaster centre in Jakarta, said: "Our prediction is that thousands have died."
On Thursday, a 6.6 magnitude quake occurred close to Padang at 8.52am local time. Indonesian media are reporting hundreds of homes have collapsed in the Jambi region.
Officials fear the death toll from Wednesday's quake could soar into the thousands, as about 500 houses and many buildings in Padang, home to 900,000 people, have been destroyed.
The ABC reports houses have also been destroyed in Pariaman, north of Padang, and inland landslides have buried more dwellings and cut off roads, making it difficult for much-needed heavy machinery to reach affected areas.
Padang, capital of Indonesia's West Sumatra province, sits on one of the world's most active fault lines along the "Ring of Fire" where the Indo-Australia plate grinds against the Eurasia plate to create regular tremors and sometimes quakes.
A 9.15-magnitude quake, with its epicentre roughly 600km northwest of Padang, caused the 2004 tsunami which killed 232,000 people in Indonesia's Aceh province, Thailand, Sri Lanka, India, and other countries across the Indian Ocean.