Jakarta: A 5.9 magnitude earthquake struck off the coast of Indonesia's Sumatra island Monday, the United States Geological Survey said, but there was no tsunami warning or immediate reports of damage.
The offshore quake hit at a shallow depth of six kilometres (3.7 miles), about 255 kilometres south of the town of Sinabang.
Shallow quakes tend to do more damage than deep tremors.
Indonesia experiences frequent quakes due to its position on the Pacific "Ring of Fire", an arc of intense seismic activity where tectonic plates collide that stretches from Japan through Southeast Asia and across the Pacific basin.
In January, more than 100 people were killed and thousands left homeless by a 6.2-magnitude quake that struck Sulawesi island, reducing buildings to a tangled mass of twisted metal and chunks of concrete in the seaside city of Mamuju.
A 7.5-magnitude quake and a subsequent tsunami in Palu three years ago left more than 4,300 people dead or missing.