TOKYO  - An earthquake with a magnitude of 7.1 hit southwestern Japan on Thursday, triggering tsunami advisories, public broadcaster NHK reported, but there were no immediate signs of major damage.

NHK earlier reported the quake had a preliminary magnitude of 6.9.

Authorities issued advisories for a one-metre high tsunami for the Pacific coast of the western islands of Kyushu and Shikoku, NHK said.

In Miyazaki prefecture on Kyushu, 20-centimetre high waves had already been observed, NHK said.

(Reporting by Kiyoshi Takenaka, Sakura Murakami; Editing by David Dolan)