david mcclure, nhk world, new york. >>> the japanese government says it's closely monitoring chinese moves in the east china sea. chinese patrol ships have been spotted just outside japanese territorial waters for 100 straight days. coast guard officials say as of wednesday morning, four of the vessels were in an area known as the contiguous zone just outside the territorial waters near the senkaku islands. chinese officials are warning them not to enter the territory. chinese patrol ships have been in the area since the middle of april. that's the longest period since the japanese government purchased the islands from a private japanese owner in 2012. officials say the ships have also repeatedly entered territorial waters and approached japanese fishing boats. japan's top government spokesperson said their continued presence in the area is a grave concern. >> translator: japanese leadership will continue to work seriously with relevant ministries to gather information to protect our territory, watersrs, and air space. the e government will do all it can to watch the area around the