An earthquake measuring 6.0 on the Richter scale rocked Indonesia's Sumatra island on Tuesday, causing panic but there were no reports of casualties or damage, meteorologists said.

The off-shore quake hit at 8:52 am (0152 GMT), with an epicentre 190 kilometres (117 miles) west of the coastal town of Sibolga in West Sumatra province, said the National Meteorology and Geophysics Agency.

The quake was felt strongly on Nias island, where an 8.7-magnitude earthquake on March 28 killed more than 900 people.

A 9.3-magnitude quake along the same fault-line as Tuesday's tremor triggered last year's Indian Ocean tsunami disaster which left more than 180,000 people dead.