Regulations Governing the Forcible Deportation of the People of the Mainland Area and the Residents of Hong Kong and Macau Article 2

The people of the Mainland Area or the residents of Hong Kong or Macau may be forcibly chased away by the competent authorities if they have entered the restricted or banned waters of the Taiwan Area.
中文原文 大陸地區人民及香港澳門居民強制出境處理辦法第2條
大陸地區人民、香港或澳門居民未經許可進入臺灣地區限制或禁止水域內,權責機關得逕行強制驅離。

English translation for reference only; the Chinese text prevails. Not legal advice.