Smartphone video posted to Twitter captured a powerful wave hitting the provincial capital, Palu, as people screamed and ran in fear.
# Government issues advisory: The authorities have issued a warning to people asking them to remain in safe areas and stay away from damaged buildings. Video captured by a local.
A 6.1 magnitude quake struck Indonesia's densely populated Sulawesi region on Friday morning, quickly followed by even fiercer 7.5 magnitude tremors which caused the tidal wave.
Lisa Soba Palloan, a resident of Toraja, around 175 kilometres south of Palu, said locals felt several quakes Friday.
We will keep you updated with the latest as it comes in.
Indonesia was rocked by a powerful 7.5 magnitude quake on September 28, just hours after at least one person was killed by a collapsing building in the same part of the country.
But by about 8:10 p.m., Hary Tirto Djatmiko, a spokesperson for the country's geophysics agency, confirmed that the quake triggered a tsunami.
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Central Sulawsi was hit earlier Friday by a magnitude 6.1 quake that based on preliminary information killed one person, injured 10 and damaged dozens of houses.
The natural disaster was larger in magnitude than the 2006 Yogyakarta quake, which measured 6.4 in magnitude, and the recent 7.0-magnitude Lombok natural disaster in August.
Indonesia's seismological agency BMKG put the magnitude at 7.4.
Indonesia is one of the most disaster-prone nations on earth.
The island of Lombok was rocked by a series of tremors in August that triggered landslides and kiled at least 460 people.
Earlier in 2004, a powerful tsunami had killed over 3 lakh people in the Indian ocean region mostly in Indonesia and caused a massive financial in the Indian states Tamil Nadu and Andhra Pradesh after a major quake off northern Malaysia.