TOKYO (Reuters) - Netflix's ( NFLX ) subscribers passed 10 million in Japan in the first half of this year with the streaming firm's Japanese-language programming grabbing attention in the growing market.

The subscriber base has doubled in the last four years and the streamer has recently released a string of well-received Japanese-language shows tackling subjects that set it apart from Japanese broadcasters.

"This year in particular we're happy that productions such as 'Tokyo Swindlers', 'The Queen of Villains' and reality-romance show 'The Boyfriend' have been watched by so many people," said Kaata Sakamoto, vice president of content for Japan.

Only two English-language series, the live-action adaptation of manga "One Piece" and the fourth season of "Stranger Things", have topped the viewing rankings in Japan since Netflix ( NFLX ) began disclosing them in 2021.

"Japan in particular is a country which wants to see a lot of its own content so we strongly feel the need to produce it," Sakamoto said.

Netflix ( NFLX ) said in September it has signed a five-year contract with Hitoshi One, the director of hit drama "Tokyo Swindlers" about a team of real estate scammers.

Streaming has encouraged consumers to watch foreign-language content with entertainment players looking to Japan in recent years.

Amazon has adapted Sega Sammy's long-running "Yakuza" game series and Reuters reported last month that Sony is in talks to acquire media powerhouse Kadokawa to bolster its entertainment portfolio.

Netflix ( NFLX ) says Japanese content is its third-most-viewed non-English content after Korean and Spanish and its anime titles were viewed more than 1 billion times globally last year.

Shares in the streamer, which has been boosted by an ad-supported tier and had 282.7 million subscribers globally at September-end, have climbed around 84% year-to-date at Monday's close.