BLANG MANCUNG, Indonesia -- The death toll from an earthquake that hit Indonesia's Aceh province earlier this week has reached 30, and police and soldiers are searching the debris for 12 other people believed missing, officials said Thursday.

Sutopo Purwo Nugroho of the National Disaster Mitigation Agency said the main focus of recovery efforts Thursday was to search for more victims, assist the injured and provide supplies for those in need. He said 275 people were injured and more than 4,300 houses and buildings were damaged in Tuesday's magnitude-6.1 quake.

Earthquakes frequently shake Indonesia, which is prone to seismic upheaval due to its location on the Pacific Ring of Fire, an arc of volcanoes and fault lines encircling the Pacific Ocean.

In 2004, a magnitude-9.1 earthquake off Aceh triggered a tsunami that killed 230,000 people in 14 countries.