Japan's Civil Aviation Bureau said on Friday it would send two investigators to Seattle as part of the probe of the battery problem on Boeing's 787 Dreamliner.

The global fleet of 50 Dreamliners, 17 of which are operated by Japan's All Nippon Airways <9202.T>, has remained grounded while investigators in Japan and the United States attempt to find out what caused one battery to catch fire on a 787 operated by Japan Airlines Co <9201.T> in Boston earlier this month, and a second battery to burn on ANA's domestic flight.

(Reporting by James Topham; Editing by Shinichi Saoshiro)