Largest earthquake since 2011 hits Japan (or maybe not)

Reports of magnitude 6.4 to 7.0 earthquake hitting Kumamoto

NHK reports that it's the strongest intensity earthquake felt in Japan since 2011. Bullet trains in Kyusho were halted after the quake.

There is no tsunami threat, according to preliminary reports.

It struck at 21:26 local time in Southern Japan.

There are no early reports of widespread damage.

Update: The USGS reports a 6.0 magnitude quake with an epicentre 8km SSE of Tamana. That's a significant downgrade.