SIBOLGA, Indonesia, March 29 -- Survivors and relief workers dug through wreckage all day Tuesday and into the night on a remote Indian Ocean island in an attempt to rescue people trapped in buildings flattened by a major undersea quake.
A United Nations official estimated that at least 500 people were killed and at least 2,000 were injured from Monday's temblor, which struck in the seabed off the coast of the Indonesian island of Sumatra. Witnesses and aid workers on Nias Island said many people in the seaside city of Gunungsitoli were buried in rubble, and fears rose that the death toll would climb. Basing their estimates on structural damage, officials said the number could reach several thousand.
Haogombowo sits with the body of his wife at a makeshift morgue on Indonesia's Nias Island, where Monday's earthquake killed hundreds.
(Suzanne Plunkett -- AP)
Photo Gallery: Hundreds were killed after a powerful underwater earthquake struck Indonesia.
Television footage shot from the air revealed widespread devastation on Nias, and fires could be seen burning. The island, a popular surfing destination, has a population of about 600,000 and is situated 45 miles from the epicenter of Monday's quake and 75 miles off the western coast of Sumatra, the major northern island of the Indonesian archipelago. Sumatra suffered major damage and loss of life from a stronger undersea quake on Dec. 26.
A damaged runway in Nias prevented airplanes from landing, but some international relief workers reached the island Tuesday by helicopter and reported dire conditions.
"Our estimate is that 20,000 people risk having no access to water," said Jeremie Delage, tsunami relief director for Oxfam International, speaking by cell phone from Gunungsitoli, Nias's main city. "It is a bit chaotic. Obviously a lot of people died in the event. There are a lot of people injured; people are trying to rescue others trapped in their houses."
The World Food Program is shipping 300 tons of food to Nias, said Imogen Wall, of the U.N. Development Program. In a telephone interview from Banda Aceh on Sumatra island, she said medical supplies and water purification equipment were top priorities.
Monday's disaster was nowhere near the scale December quake, which spawned a tsunami in the Indian Ocean that killed an estimated 280,000 people in 11 countries. Though warnings were issued, including a first-ever alert issued to 11 countries in the region by Japan's Meteorological Agency, Monday's magnitude 8.7 quake did not generate tsunamis.
Indonesia's Metro TV reported that there were indications of destruction on neighboring islands. About 100 people died on the smaller island of Simeulue, Metro TV said, quoting an unidentified official there.
Dave Jenkins, a New Zealand physician who runs the relief agency SurfAid International, said there had been no contact with the Banyak Islands, home to about 10,000 people. The islands are located close to the quake's epicenter.
In Washington, President Bush offered condolences to quake victims. "The people of Indonesia can know as well that they have our prayers and that our government is ready to assist," he said.
At the State Department, spokesman J. Adam Ereli said there were no plans to tap into the nearly $1 billion pledged for countries affected by the December tsunami to help the victims of the latest quake. He said the U.S. ambassador delivered $100,000 from his emergency fund to CARE and Save the Children to respond to immediate needs on Nias and Simeulue.
"Early estimates are of hundreds dead and as many as 80 percent of buildings damaged or destroyed on the two islands," Ereli told reporters. Representatives of the U.S. Agency for International Development based in Aceh province on Sumatra also traveled to the islands Tuesday to conduct a preliminary assessment of the damage.
In Gunungsitoli, Delage said the destruction was considerable, but that he had not been able to assess damage elsewhere on the island.
"Everybody fled to the hills" after the quake, he said, recalling the destruction from December's quake, whose epicenter was about 120 miles farther northwest. "A lot of them are still in the hills and sleeping in the open. They have no shelter, no food and no water." He said most shops had been destroyed. In addition, he said there were aftershocks with magnitudes of up to 6, which qualify as large earthquakes on their own. Residents said they feared the aftershocks would topple already weakened structures. Those interviewed said the quake seemed more intense than the one three months ago, which led to more than 100,000 deaths in Aceh. On Nias, the earlier quake and tsunami killed 340 people and left 10,000 homeless.