Quake and Tsunami Death Toll Could Be in the Thousands

Thousands are believed to be buried under rubble on Pacific islands ravaged by earthquakes this week and many more were washed out to sea by a resulting tsunami, relief workers estimated today.

The tsunami death toll was estimated to be about 150 in the Samoan islands while Indonesian officials put the casualty rate from earthquakes at 1,100, the Associated Press reports.

But Josettte Sheeran, excutive director of the World Food Program, estimated that those numbers will rise dramatically, and said the latest "wave of devastation" that rippled through the islands in recent days was "a distressing reminder of the destruction which occurred during the 2004 tsunami" which killed hundreds of thousands over several continents.

VIDEO: Two earthquakes hit Indonesia as death toll from Samoas tsunami rises.Play

Sheeran said quakes that shattered buildings in Indonesia caused widespread destruction. "Thousands are believed to be buried under the ruins," she said.

Hospitals are overflowing with the injured and the region's mosques are filled with the homeless whose neighborhoods have been destroyed.

"In the Samoan islands, thousands of people are still trapped under the rubble and many have been swept out to sea," she said. Homeless survivors are being drenched with heavy rains.

The Phillipines was also rocked by flooding and the WFP said they need to gear up to feed 1 million people.

"When nature strikes with such force, the world must come together," Sheeran said.

The Indonesian city of Padang is still recovering from two powerful earthquakes, one of which flattened a school where 30 children are still missing.

VIDEO: Explaining tsunamisPlay

The first earthquake -- registering a massive 7.6 magnitude -- came Wednesday night, collapsing at least 500 buildings and badly damaging and burning others.

Less than 24 hours later, another quake struck Indonesia, this time weaker, but still powerful.

Rescue efforts have been hampered, in part, by downed communications.

Samoan Tsunami Clean-Up

As the Indonesians took stock of the damage, the island nation of Samoa began recovering from the tsunami earlier this week that killed more than 100 people after a separate earthquake sent a wall of water cascading into the Pacific islands.

Relief supplies including clothes, cooking tools and food have just started reaching residents on the country's hard-hit southern coast.

As some clamored for supplies, a team of volunteers spent time scouring the tattered remains of a village looking for a lost 4-year-old boy.

"If he's still inside the house, maybe he's crushed inside," one of the searchers said.

Men nearby dug a grave for another village's 78-year-old matriarch -- her body was found at sea.

"It's a feeling of sadness that nobody can read except God in your heart," a local woman said. "And I feel like I'm one of them -- one of the people who are dead."

Experts Say Seismic Shifts Can Occur in Clusters

While it is not routine for multiple major earthquakes to wreak havoc on two countries at the same time, seismologists say they aren't completely surprised.

"The area around Samoa and the area off the coast of Sumatra are both highly seismically active," said Stuart Sipkin, a USGS geophysicist with the National Earthquake Info Center. "They do tend to cluster and so it's very often you'll see large earthquakes happening in a short period of time."

Even California saw an earthquake early this morning, as 5.1-magnitude quake hit central California's Death Valley. No injuries were reported.

ABC's "Good Morning America" anchor Sam Champion said strings of seismic activity are typically started when the plates that constantly press against each other start to shift.

"At some point, one's going to give," he said, noting that 80 to 90 percent of all earthquakes occur in the Pacific.

For information on how to help tsunami victims, you can visit the World Food Programme, or call (866) 929-1694.