JAKARTA, Sep 20 (Reuters) An undersea earthquake measuring 6.7 on the Richter scale jolted West Sumatra today, striking in the same area as last week's powerful tremor, Indonesia's meteorology agency said.
The quake struck at 1401 IST at a depth of 76 km, but the agency did not issue a tsunami warning in the notice it sent through a mobile phone message. The U S Geological Survey put the strength of the quake at magnitude 6.6.
There were no immediate reports of any damage after the quake, epicentred in the Mentawai island chain, famous of its surfing sites.
More than 20 people were killed when the 8.4 magnitude earthquake hit the area last week, which was followed by a series of strong aftershocks, setting off tsunami warnings in Indonesia and other countries in the region.
Indonesia, which is situated in a belt of intense seismic activity known as the ''Pacific Ring of Fire'', was hit by a huge earthquake in December 2004, triggering a devastating tsunami in the Indian Ocean, which killed more than 230,000 people in the region, including 170,000 Indonesians.
REUTERS SKB HT1455