An aerial view shows the tsunami devastated Sabeugunggung village in the Metawai islands, West Sumatra, on October 31, 2010 six days after a 7.7-magnitude quake-triggered tsunami hit the area. Indonesia ramped up aid operations Sunday for victims of last week's devastating tsunami, as the toll climbed despite the discovery of 135 traumatised villagers who were feared dead. AFP PHOTO / Bay ISMOYO (Photo credit should read BAY ISMOYO/AFP/Getty Images)
Tsunami waves up to half a metre (1.6 feet) high "will possibly affect several areas in Indonesia" from early Thursday, said disaster agency spokesman Sutopo Purwo Nugroho.
The quake struck late Tuesday, sending tsunami waves of more than two metres crashing into Chile's northern coast. At least five people have been killed, panicked crowds have fled and some northern areas of the country have been declared a disaster zone.
Nugroho said that the first tsunami waves could arrive at around 5:00 am Thursday (2200 GMT Wednesday) in the eastern region of Papua, and that authorities in 19 provinces of Indonesia -- which is thousands of miles (kilometres) away from where the quake struck -- had been alerted.
"We are urging the provincial and district governments within these areas to take precautions by urging people to stay away from beaches," he said in a statement.
Other areas that could be affected by the tsunami include parts of the main island of Java, the resort island of Bali, central Sulawesi island, and the Indonesian part of Borneo island, he said.
"People must remain calm," he said, adding that no one had so far been evacuated.
Indonesia, which is frequently hit by earthquakes and has scores of active volcanoes, is particular vulnerable to even small tsunamis as many people on the archipelago of more than 17,000 islands live in poor, coastal communities.
More than 170,000 people were killed in Aceh province on western Sumatra island in 2004 when it was hit by a huge quake-triggered tsunami, which also left thousands dead in other countries around the Indian Ocean.
Authorities have well-developed early tsunami warning systems and tend to be cautious.
However in New Zealand and Australia, southeast of Indonesia and with Pacific coastlines, authorities said there was no threat of a tsunami.
The Australian Tsunami Warning Centre said there was "no tsunami threat to Australia", while New Zealand emergency authorities said "the earthquake is unlikely to have caused a tsunami that will pose a threat to New Zealand".