The United States Geological Survey has reported a strong 6.2 magnitude earthquake in southern Mexico.
The second quake was centred 355 km south-east of Mexico City, 120km west-south-west of the colonial city of Oaxaca. It struck at a depth of 20km in the early morning local time.
The USGS initially reported the quake as of magnitude 6.5, but later revised the figure to 6.2.
Reports say it shook buildings in the capital and some people fled their homes in the city centre. Power has been cut in some areas.
One man is reported to have died.
Earlier a 6.3 magnitude tremor struck 360km south-west of Fiji. It was at a depth of 536km and hit at 4.30pm local time. No tsunami warning was issued.