Another major earthquake strikes Indonesia

[Benhamin]

CNN) -- Officials in Thailand and Sri Lanka report that residents are evacuating coastal regions in the Indian Ocean after an earthquake with a preliminary magnitude of at least 8.2 struck off the coast of Indonesia Monday.

In Thailand, thousands of people in the six provinces affected by the December 26 tsunami were moving to higher ground or 2 km (1.25 miles) inland, the governor of Phang Nga province said.

Sri Lanka also issued a warning that the earthquake may spawn a tsunami that would reach Sri Lanka's shores by about 3 a.m. Tuesday (4 p.m. ET Monday) and urged those living in low lying areas to move to higher ground.

The National Oceanic and Atmospheric Administration has recommended residents within 1,000 kilometers (620 miles) of the epicenter to evacuate coastal regions. The quake was centered on the same fault line where a December 26 earthquake launched a tsunami that killed at least 175,000 people.

Prass Prawoto, an aid worker in Banda Aceh -- which was severely damaged by the December 26 tsunami and quake -- said Indonesians were moving to higher ground, fearing a repeat of the earlier tsunami. But, he said, he had not heard of any injuries.

CNN producer Kathy Quiano, watching television reports from Jakarta, said there was widespread panic in Banda Aceh, as residents rushed inland.

A number of traffic accidents occurred as a result, and people were injured, she said, citing local television reports. "People are closely watching for the water that may come in," she said. Electricity and phone service were out in major sections of Banda Aceh, Quiano said.

Charles McCreary, director of the Pacific Tsunami Warning Center, said scientists believed another tsunami is possible, but he could not be certain if the quake, which was 203 kilometers (126 miles) from Sibolga on Sumatra Island, would cause another deadly wave.

Experts agreed the quake was massive. The U.S. Geological Survey put the magnitude at 8.2; the Pacific Tsunami Warning Center said it was 8.5.

"This earthquake has the potential to generate a widely destructive tsunami in the ocean or seas near the earthquake," NOAA said in a statement on its Web site. "Authorities in those regions should be aware of this possibility and take immediate action."

Asked whether evacuations are taking place, U.S. Geological Survey spokesman Don Blakeman said, "I certainly hope so."

Thailand's chief meteorologist, Smigs Bsammasaroj, issued a warning that the quake could bring a tsunami to its southern provinces. The warning, which was carried on national television, cautioned people in the six provinces to be careful and vigilant, but did not order evacuations.

USGS spokesman Doug Blake said there had been no reports of tsunami activity nearly 90 minutes after the quake struck.

"We're still waiting for any kind of reports," he said.

"At this point in time we don't know what type of fault occurred ... and that is critical information we just don't have yet," he said. "It is in the aftershock zone of the December 26 quake. It's a little bit south, but it's on the same fault."

The quake occurred at 11:09 a.m. ET (1609 GMT), and is considered a "great" earthquake, the largest of seven grades.

The grades are very minor, minor, light, moderate, strong, major and great.

Tsunamis are distinguished from normal coastal surf by their great length and speed. A single wave in a tsunami series might be 160 kilometers (100 miles) long and race across the ocean at 960 kph (600 mph).

When it approaches a coastline, the wave slows dramatically, but it also rises to great heights because the enormous volume of water piles up in shallow coastal bays.

The December 26 quake, measured at magnitude 9, triggered a massive tsunami that devastated coastlines in nearly a dozen nations in Africa and Asia.

[Benhamin]

They had a 6.0 aftershock too.

USGS says that the original quake measured as high as 8.7.

[M. Brown]

I heard about this this morning. Shocking