Japan accuses China of sailing into its waters just days after a Chinese spy plane violated Japanese airspace

• Japan says a Chinese Navy survey ship sailed into its territorial waters on Saturday.
• The incident comes just days after a Chinese military spy plane flew into Japanese airspace.
• China asserted that the two incidents weren't linked, adding that the ship's passage was legal.

Japan accused China of sailing into its territorial waters just days after one of Beijing's spy planes violated Japanese airspace for the first time.

The incidents, which China asserted aren't linked, are sparking further tensions between the two nations.