TOKYO, Jan. 5 (UPI) -- More than 100 Chinese vessels trespassed into Japan's territorial waters near the Senkaku islands in 2016, and in 2017 incursions have been taking place daily, Japanese newspaper Mainichi Shimbun reported.
A total of 121 vessels sailed near the disputed Senkaku Islands, also known as the Diaoyutai Islands in China. It is the second-largest annual number of Chinese ships entering disputed areas since Japan announced the nationalization of the Senkakus in September 2012.
In 2012, Tokyo purchased three of the five uninhabited islands in the Senkaku island chain, a move that has caused friction between the two countries and has resulted in the continued presence of Chinese ships in the area.
By contrast, only two Chinese vessels were reported in the area as recently as 2008.
A total of 188 unauthorized Chinese ships were seen in Japan's waters from 2012 to 2013 after the islands were nationalized, but 2016 marks the first time in recent years when the number of ships surpassed 100, according to the report.
More ships of Chinese origin are sailing in the waters daily, the report states.
According to NHK, four Chinese ships entered waters located about 14-27 miles from Japan-claimed territory, and Tokyo's coast guard has been warning Chinese vessels to not approach Japanese territorial waters.