A large earthquake has struck off the coast of northern Sumatra sparking tsunami warnings across the region.
The quake struck 125 miles northwest off Sibolga, Sumatra or 880 miles northwest of the Indonesian capital of Jakarta, close to where the December 26th quake triggered a devastating tsunami.
The quake has caused widespread panic across the region and large scale evacuations in the coastal regions of Indonesia, Thailand, Sri Lanka and Malaysia have been reported.
As yet there have been no reports of any tsunamis.
The Pacific tsunami warning center said Sumatra has the potential to cause a "widely destructive tsunami" and authorities should take "immediate action," including evacuating coastlines within 600 miles (1,000 km) of the epicenter.
Initial data indicated the magnitude was 8.5 on the Richter Scale. This was later upgraded to 8.7.
"Authorities can assume the danger has passed if no tsunami waves are observed in the region near the epicenter within three hours of the earthquake," the center said in a statement. The National Weather Service's Pacific Tsunami Warning center is based in Hawaii.
Several reports said the tremors from the quake - which were felt as far as Malaysia - were stronger than the December 26th earthquake.
The quake struck between the Sumatran cities of Padang and Medan at around 11.15 pm local time and lasted up to three minutes, said Indonesia's Meteorological and Geophysics Office.
Power blackouts and major panic ensued, local officials told AFP news agency.
Tens of thousands of people are understood to have ran out of their homes in many parts of Sumatra. But there were no immediate reports of casualties.
Widespread damage has been reported on the small island of Nias which is closest to the epicentre.
Thailand has issued a tsunami warning for provinces along its Andaman Sea coast after tremors were felt as far away as Bangkok.
"Please evacuate to higher places now. There is a strong chance of another tsunami," an official told Thai radio.
"About 3,000 to 4,000 tourists and locals have been evacuated from Patong and Kamala beaches to higher places," Phuket deputy governor told reporters.
"We've told them to take their valuable belongings and to go to higher places," he added.
Sri Lankan officials have warned of an impending natural disaster.
The government in India's remote Andaman and Nicobar islands said it had issued a preliminary tsunami warning this evening but was not yet evacuating people.