The Pacific Tsunami Warning Centre has not issued an advisory on the quake, which hit at 3:28am (local time) about 35 kilometres south-west of the coastal city of Concepcion at a depth of 17 kilometres.
The quake struck close to the epicentre of a massive 8.8-magnitude earthquake that rocked Chile on February 27, sparking a huge tsunami that killed 521 people and swept away entire villages.