Authorities revised up the death toll from a powerful 7.0 magnitude quake in Kumamoto prefecture in southwestern Japan to 34, with another 89 injured. Japan is one of the world's most seismically active countries, sitting on top of four major tectonic plates along the western edge of the Pacific "Ring of Fire." Key points and original sources are listed below.

• Authorities revised up the death toll from a powerful 7.0 magnitude quake in Kumamoto prefecture in southwestern Japan to 34, with another 89 injured.S1

• Japan is one of the world's most seismically active countries, sitting on top of four major tectonic plates along the western edge of the Pacific "Ring of Fire."S2

• The death toll from a strong earthquake that struck southwestern Japan climbed to 14 on Wednesday.S3