JAKARTA - A tsunami hit the city of Palu and the fishing town of Donggala in Sulawesi Island after a strong 7.5-magnitude earthquake struck the area on Friday (Sept 28).
Some people were killed as buildings collapsed, the National Disaster Management Agency (BNPB) said.
The earthquake struck at 6.02pm in Palu, with an epicentre located 26km north-east of Donggala Regency, Central Sulawesi, and a depth of 11km.
The Meteorology, Climatology and Geophysics Agency (BMKG) issued a tsunami warning five minutes later for residents of Central Sulawesi and West Sulawesi provinces.
The tidal waves brought by the tsunami reached 1.5 metres, BMKG chief Dwikorita Karnawati told a press conference.
"When the waves receded, some boats returned to the land and we ended the tsunami alert," she said.
BMKG put the magnitude of the quake at 7.4, while the US Geological Survey said it was 7.5, after first saying it was 7. 7.
A video taken with a mobile phone, which has been circulating in Indonesia, shows a number of small restaurants close to Palu Grand Mall were carried away by the waves, while the nearby Baiturrahman Mosque was also hard hit.
President Joko Widodo on Saturday extended his condolences for those affected by the tsunami in Donggala, Palu, and the surrounding areas.
He cited difficulty in contacting the local governor as communication has been disrupted but he said he has ordered his Chief Security Minister Wiranto to coordinate with the BNPB, and for Armed Forces chief Hadi Tjahjanto initiate the emergency rescue and evacuation process, as well as to prepare basic needs for people affected by the earthquake and tsunami.
"We hope that tomorrow (Saturday) we can get more detailed information," added Mr Joko. "I will continue to monitor (the situation) at every minute, every hour but for all the people especially those in Donggala, Palu, and the surrounding areas, please remain calm and alert, we will handle this together."
Indonesia sits on the Pacific's "Ring of Fire", making it vulnerable to earthquakes as well as volcanic eruptions.
In December 2004, a magnitude-9.1 earthquake off the coast of Sumatra triggered a tsunami across the Indian Ocean that claimed 226,000 lives in 13 countries, including over 120,000 in Indonesia.
The tsunami and the latest earthquake on Friday followed a magnitude-6.0 quake that occurred at 2pm in Palu, killing one person, injuring 10 and destroying dozens of houses, according to the BMKG.
BMKG spokesman Hary Tirto Djatmiko said that Mutiara SIS Al-Jufrie Airport in the provincial capital of Palu has been closed temporarily until at least Saturday night as the strong quake left cracks on the runway.
Mr Rahmat Triyono, who leads the earthquake and tsunami centre at the BMKG, said the agency continues to monitor aftershocks, which already reached 31 as of 10pm in Palu.
BNPB spokesman Sutopo Purwo Nugroho said the telecommunication network was down and there was a power outage, which made it difficult to assess the damage. The regional unit of the agency has activated its mobile satellite to help the communication on the ground, he added.
The greatest casualties caused by the earthquake may be found in Palu and areas north of the city until Donggala Regency, including Parigi and Kasimbar, where the disaster was felt with strong intensity, according to BNPB's estimate.
"We've coordinated with the Energy and Mineral Resources Ministry. The repair of electricity network by (utility company) PLN should become a priority," Mr Sutopo told MetroTV.
In July and August, a string of earthquakes rocked Indonesia's popular tourist destination Lombok Island, which is hundreds of kilometres southwest of Sulawesi.
