Japan　observed small tsunamis at Izu Islands, south of central Tokyo, on September 24.

Japan Meteorological Agency warned early in the morning that there could be tsunamis due to an earthquake.Tsunami advisories were issued for the Izu and Ogasawara Islands,following a magnitude 5.8 earthquake off the Tori-shima Island around 8:14AM local time. Tsunami of 50 centimeters was observed in Hachijojima, and also a 20 centimeter tsunami at Kozu island, the islands which belongs to Tokyo prefecture. 

The agency said that the mechanism of the quake is yet unknown, but said that about1,800 meters worth of sea surface discoloration was observed on September 19 around Sumisujima island (or Smith Rocks), an undersea volcano near the epicenter of the quake.An eruption warning was issued on September 19, calling for caution in the surrounding waters.Discoloration around the area was observed in July of this year as well.

No damage has been reported from the tsunamis, and a tsunami advisory was lifted in the early afternoon.