Indonesia Earthquake: As a people, they already had little - now they are left with nothing

In the morning, Salim retrieved the lifeless body of his three-year-old son, Sihman, from the ruins of their brick and bamboo hut. In the afternoon, he buried him, digging the grave himself. As night fell, he searched through the rubble of his former home for scraps of food. "I have lost everything," he said.

Salim's family lived in Bantul, a semi-rural district just south of the Indonesian city of Yogyakarta, in the heartland of the island of Java. Bantul, a patchwork of villages where farmers grow rice, corn and chillies, was hardest hit by the earthquake that struck the area on Saturday morning. More than 80 per cent of buildings were flattened.

The total death toll stood at more than 4,600 last night, with up to 20,000 injured and more than 100,000 left homeless. As rescue teams continued to look for survivors, the international community pledged millions of pounds in aid, and relief agencies sent medical teams and emergency supplies.

Hospitals in Yogyakarta, a gracious and laid-back city that is home to one of Indonesia's oldest royal families, are overwhelmed by the scale of the disaster. Yesterday, as ambulances ferried the dead to the morgues, the injured were treated in emergency wards set up in the open air. Hospitals were desperately short of surgeons. The Regent of Bantul, Idham Samawi, told the Jakarta Post that local authorities had broken into their own pharmaceutical warehouses because they could not find the keys. "But now all the drugs have been used up," he said.

In the city itself, most buildings still stand, although many have cracked facades and caved-in roofs. At the 9th-century Prambanan Hindu temple complex, stupas were blasted off and parts of Yogyakarta's centuries-old royal palaces were damaged.

But it is outside the city, to the south and to the east, that the impact of the quake is most visible. The road to Bantul is lined with blue tents and tarpaulins, donated by aid agencies. As rain sheeted down last night, the homeless and bereaved huddled together beneath the shelters.

Power and telephone lines are still down, and clean water is a problem, with all 12 water distribution systems in Bantul either destroyed or not functioning, according to Unicef. Villagers said they were also short of food.

But it is not only material concerns that trouble them. They fear another earthquake. Even those with homes still standing spent Saturday night outdoors, sleeping in any open space available - on the streets, in cassava fields and even on the narrow pathways between the paddies. Dozens of aftershocks have fuelled their jitters.

When the locals were jolted from their beds shortly before 6am, many thought Mount Merapi, a nearby volcano that has rumbled for weeks, had erupted. Although they live in a region of intense seismic activity, they had never experienced a quake of that magnitude.

Haunted by memories of the Boxing Day tsunami that devastated Indonesia's Aceh province in 2004, many people feared a tidal wave would roll in from the Indian Ocean, a few miles to the south. They fled north, towards Merapi - unsure whether the sea or the volcano would prove more treacherous. In the event, both were calm, although Merapi continued to blow ominous clouds of gas and ash into the air yesterday.

The volcano's recent activity meant that aid agencies, who were on hand to help residents evacuated from its slopes, already had a presence in the area. Now they find themselves dealing with an emergency that was unforeseen, and on a different scale.

Britain pledged yesterday to give £3m in aid, and the US, China, France, Russia and Australia have also offered assistance. John Budd, of Unicef in Jakarta, said the agency had been geared up for relief operations in the event of Merapi erupting. "We will be able to provide food, tents, collapsible water tanks and health kits," he said.

Tents, however, are in short supply, with 20,000 people who lived in the shadow of the volcano already moved off the mountain to emergency shelters. On the road to Bantul, one village head complained that 33 families were living beneath one large tarpaulin.

Bantul is a heavily populated area, home to factory workers who commute to Yogyakarta, as well as farmers who sell their produce at the city's market. Most families lived in flimsy dwellings with wooden roofs. When the earth trembled, their houses collapsed. Many of the dead were buried in their beds.

Village after village in the area was laid waste, and Bantul is now a ruined landscape. Salim, like many people in this deeply religious part of Indonesia, interpreted the quake as a manifestation of the wrath of Allah. He pointed to a series of natural disasters that have affected the country, including the tsunami. "We have done something to anger him," he said. Sitting beside him, his wife rocked back and forth, too grief-stricken to speak.

In the village of Jamprit, a man called Poniran told how he dug his five-year-old daughter, Ellie, out of the rubble of her bedroom. She was alive when he lifted her out but died in his arms while waiting for treatment in an overcrowded hospital, along with hundreds of others. Her last words, he said, were "Daddy, Daddy". Poniran said: "I have to start my life from zero again."

These were people who had little. Now they have almost nothing. Yesterday they were scrabbling through the remains of their homes, salvaging what they could - a hammer, tins of tuna, some family photographs. They made soup from vegetables and a few chunks of meat, and a group of women cooked catfish caught in a nearby pond.

Budi Wiyana, 63, whose house was destroyed, said: "We're short of everything - clothes, food, water, all are gone. We are poor people, but our lives still matter." Most of the dead were buried in village graveyards within hours of the disaster, in line with Islamic tradition. The death toll is expected to rise, as more bodies are excavated.

Some locals are still hoping against hope that missing relatives may be found alive. Volunteers from the Indonesian Red Cross, assisted by Kopassus special forces troops, searched the wreckage of buildings for survivors yesterday. "We need more heavy equipment and excavators," said one.

The ancient Buddhist temple complex of Borobudur, near Yogyakarta, is one of Indonesia's biggest tourist attractions, visited by one million people a year. Foreigners are also attracted to the city by its many language schools that offer intensive tuition. Yesterday it appeared, however, that only one foreigner - a Dutchman, as yet unnamed - was among the dead.

Borobudur, which is the biggest Buddhist monument in the world, appears to have survived intact. But the world-renowned 9th-century Prambanan temple complex, which like Borobudur is a United Nations world heritage site, was damaged in the quake which sent intricate carved reliefs crashing to the ground and destroyed years of restoration work in less than a minute.

Seismic forces that shape the world

By Steve Connor, Science Editor

What causes earthquakes?

The earth's crust is composed of giant, slowly moving tectonic plates. On a fault line, these plates gradually slide over one another, but they can get stuck at their edges due to friction, which causes a build-up of stress. This pent-up energy can be suddenly released when the plates begin to move past one another again, causing the ground to shake violently and generatingenergy waves that can travel round the world.

In short, an earthquake is a sudden slip of the land lying on a fault line.

How did this earthquake happen?

The Indonesian island of Java is dominated by the movements of the Australian tectonic plate, which is sliding underneath the Sunda plate at a rate of about 6 centimetres per year. The Australian plate dips north-northeastwards under the Sunda plate from the Java trench, a deep valley under the sea off the island's western coast.

Java is sitting on the Sunda plate, which is being lifted by the Australian plate sliding beneath it at depths of between 100 and 200 kilometres. Further north, the Australian plate reaches depths of 600 kilometres. The earthquake on 26 May occurred at a relatively shallow depth within the Sunda plate and well above the deeper Australian plate. It measured 6.3 on the Richter scale.

Was the earthquake linked with the eruption of the Merapi volcano further north?

In general terms the seismic forces that cause earthquakes are separate from the magmatic forces that generate volcanic eruptions. "Earthquakes may occur in an area before, during and after a volcanic eruption but they are the result of the active forces connected with the eruption, and not the cause of volcanic activity," according to the US Geological Survey (USGS).

In this case, the jury is still out on whether the earthquake late on Friday had anything to do with the on-going volcanic activity on Merapi, which is tens of kilometres further north.

"We do not know if there is a direct link," said the USGS over the weekend. "The occurrence of shallow-focus earthquakes near volcanoes is not unusual worldwide. Sometimes the association of earthquakes and volcanic eruptions is so close in space and time that it is clear that the earthquakes are triggered by the magmatic processes that are causing the eruption. In the cases of many earthquakes that occur in the general vicinity of volcanoes, however, there are not obvious links to volcanic eruptions."

One possibility is that there is an underlying tectonic process behind both the seismic activity that caused the earthquake and the magmatic forces that generated the volcanic eruption.

Is it true that we are having more of these big earthquakes now than in the past?

There is no evidence that earthquakes are becoming more common. In fact the USGS said it has recorded fewer of the really big earthquakes - magnitude 7.0 or greater - over the past 20 years. The number has gone down very slightly from about 20 in 1970 to about 18 in recent years.

What has changed is the ability of scientists to detect earthquakes and the ability of the media to report from some of the most remote regions of the world. Both could make it appear as if the Earth is becoming more seismically active.

In 1931, for instance, there were about 350 seismic recording stations in the world and they were limited in how fast they could transmit information. Now there are more than 4,000 stations in a global network that can, with the help of satellites and modern telecommunications, transmit data across the world within seconds of an earthquake occurring.