If all 644 are confirmed dead — as is likely — the death toll in the disaster would jump to more than 1,300. The government's death toll currently is 715, with most casualties reported from the region's biggest city, Padang, where aid efforts are currently focused.
More than 3,000 people were listed as missing before the news about the obliterated villages emerged.
The United Nations said in a report that more than 1.1 million people live in the 10 quake-hit districts. It said 10,00 houses collapsed, 19 public facilities were badly damaged, 50 schools destroyed and more than 80 mosques severely damaged.
Rustam Pakaya, head of the Health Ministry's crisis center, told The Associated Press that the villages of Pulau Aiya, Lubuk Lawe and Jumena in Padang Pariaman district were completely wiped out by the landslides.
He said 400 people were attending a wedding in Pulau Aiya when the quake set off a landslide. In Indonesia's rural areas, weddings are often communal affairs open to the entire village.
"They were sucked 30 meters (100 feet) deep into the earth," Pakaya said. "Even the mosque's minaret, taller than 20 meters (65 feet), disappeared."
He said about 244 others were buried in Lubuk Lawe and Jumena villages. Only 26 bodies had been extricated, he said.
At a fourth village, Limo Koto Timur, a giant section of a hillside was swept away and the remains of destroyed houses protruded from the mud. The village's population was not immediately available.
The ruins of other tin-roofed homes hung precariously over the edge of a huge crevice torn through rice fields and forest. Roads were gone and palm trees had been uprooted and swept downhill, leaving patches of brown earth where villages once stood.
El-Mostafa Benlamlih, the U.N.'s humanitarian coordinator for Indonesia, told the AP that 200 houses were swept away in Pulau Aiya.
The immediate medical needs from the quake were being met, but aid efforts are "still concentrated in Padang area," with outlying areas still short of aid, Benlamlih said.
He said aid agencies would focus on restoring public utilities, sanitation and preventing disease.
Elsewhere, disappointed rescue workers were unable to locate survivors buried under a collapsed hotel in Padang after one sent a cell-phone text message to a relative Friday saying he and some others were alive.
Frantic rescue efforts came to naught Saturday as sniffer dogs failed to detect life.
After several hours of digging through blocks of concrete, steel and bricks, rescue workers gave up. Padang police chief Col. Boy Rafli Amar told reporters, "So far rescuers have found nothing."
Hidehiro Murase, head of a Japanese search dog team, said its search had been fruitless.
"We did an extensive search this morning, but there were no signs of life. Our dogs are trained to smell for living people, not the dead, and they didn't sense anything," he told the AP.
The U.N. said there are sufficient fuel stocks in the area for four days, but the road to the depot was cut off by landslides and shortages had inflated gasoline prices six-fold.
Areas with "huge levels of damage to infrastructure were in need of basic food and tents for temporary shelter," it said.
Vice President Jusuf Kalla estimated that the quake damaged about 17 percent of buildings in the worst-hit areas.
He said the recovery operation would cost at least $400 million.
Military and commercial planes shuttled in tons of emergency supplies.
Millions of dollars in aid and financial assistance came from Australia, Britain, China, Denmark, the European Union, Germany, Japan, Malaysia, the Netherlands, Singapore, South Korea, Switzerland and the United States, Indonesian officials said.
Wednesday's quake originated on the same fault line that spawned the 2004 Asian tsunami that killed 230,000 people in a dozen nations.
