Whole villages in Indonesia's quake zone were found obliterated by landslides yesterday, as rescuers searched desperately for up to 4,000 people believed to be still trapped in rubble.

The full extent of the damage from Wednesday's 7.6-magnitude earthquake emerged as attention turned to the hundreds of villages in the hills outside Padang, a devastated city of one million at the centre of rescue efforts.

AFP journalists travelling from the coastal city on Sumatra island to the surrounding mountains encountered dozens of crumbled houses on the steep roads, and then four villages buried entirely by landslides.

Search and rescue officers from the local government said that up to 400 people could have perished in the four hillside villages alone, including a wedding party of 30 that was preparing for a ceremony nearby.

"The difficulty in this rescue operation is that the houses are buried under the soil as much as four metres deep," the officer named Topan told AFP. "So far we have been using our hands to dig."

One body was seen lying in a stream nearby, but he said he expected many more would be found. The 100-strong rescue team was unable to bring in heavy machinery because of the broken, narrow roads.

Another official said about 600 people were missing in landslides northwest of Padang. "We've only found three dead," local health ministry crisis centre chief Jasmarizal told AFP.

Bob McKerrow, head of the Indonesia delegation of the International Federation of the Red Cross and Red Crescent Society, said aerial photos showed the huge extent of the damage in the mountainous outlying regions.

He said hundreds of villages were in the disaster zone, and that the few he had visited had all reported deaths and serious injuries.

"Typically in every village, there's an old woman with a broken back, with a gash on her arm and she's not moving. That's why we're sending in helicopters with medical teams," he told AFP.

In Padang, where hardly a single building was left undamaged, rescuers were racing against time to haul any survivors from schools, hotels and homes reduced to tangles of concrete and rubble.

Specialist teams from Australia, Britain, Estonia, Japan, Russia, Singapore, South Korea, the United States and the United Arab Emirates have arrived or are travelling to the scene to help overwhelmed and exhausted local teams.

Hope was raised yesterday when police said they had received a text message from inside the ruined Dutch colonial-era Ambacang hotel, which has become a focal point for operations, drawing a crowd of hundreds.

"I think there could still be survivors," said Yoshiaki Shimazu, the leader of a specialist team from Japan with rescue dogs at the scene. "The way the building fell, there could be voids."

David Lange, a doctor for the Surf Aid medical organisation, was inside the the building as it caved in and sent colleagues a dramatic description of his escape that was passed on to AFP.