An earthquake of magnitude 5.8 on Monday struck West Sumatra near Pariaman, Indonesia.
This is what the United States Geological Survey (USGS) said, adding that the quake was at a depth of 11.9 kilometres. It did not trigger a tsunami warning.
Three consecutive earthquakes struck the area with increasing intensity since the early hours of Monday, with a 5.2-magnitude tremor recorded before dawn, followed by a 5.4-magnitude quake less than an hour later.
The 6.4-magnitude earthquake was felt strongly for several seconds by residents in the Mentawai islands, in the provincial capital of Padang, and in the surrounding mountainous area of Bukitinggi, the disaster agency said in a statement.
The agency said there were no reports of casualties but there was minor damage to buildings on Siberut island.
Separately, Novriadi, a local disaster official in the Mentawai islands, told Reuters that residents in several villages had been evacuated to higher ground and a local church, school and health facility had been slightly damaged.
The disaster agency urged the public not to panic and warned of the potential for aftershocks.
Padang was struck by a 7.6-magnitude earthquake in 2009 that killed more than 1,100 people, injured many more and caused widespread destruction.