SUMATRA (REUTERS) - An earthquake with a magnitude of 6.0 struck off the Indonesian island of Sumatra on Wednesday (June 13), the US Geological Survey said, but there were no initial reports of damage or injury.

The shallow quake struck 246km south-west of Padang on Sumatra, the USGS said.

There was no immediate warning from the Hawaii-based Pacific Tsunami Warning Centre.

The quake was later downgraded to 5.8 by the USGS.