A police emblem is seen on a glass door in this file photo. (The Korea Herald) A Chinese national was arrested after entering South Korean territorial waters on a rubber boat off the coast of Taean, South Chungcheong Province, the Korea Coast Guard said Tuesday.According to the Taean Maritime Police Station, a suspicious rubber boat was spotted at around 9:36 p.m. Monday about 18 kilometers northwest of West Gyeongnyeolbi Island, off Taean County. The location was about 3.6 kilometers inside South Korea’s territorial waters.The boat was first spotted by the captain of a 20-ton fishing vessel operating in the area, who reported it to the fisheries safety communications office. The Coast Guard dispatched a patrol vessel to the scene after receiving the report.The rubber boat was about 3.3 meters long and equipped with a 9.9-horsepower engine. The man was the only person aboard.The Coast Guard arrived at the scene about one hour and five minutes after receiving the report and took the man into emergency custody. The fishing vessel reportedly remained near the rubber boat and monitored the situation until the Coast Guard arrived.Authorities booked the man on suspicion of violating the Immigration Act and are investigating why and how he entered South Korean waters.