China's coast guard said Sunday it will strengthen its law enforcement activities and carry out regular patrols around a small group of Taiwanese-controlled islands off the Chinese coast as tensions rise over the deaths of two Chinese nationals.

Taiwan on Thursday defended the actions of its coast guard after two people on a Chinese speedboat, which got too close to a front-line Taiwanese island, died when their boat overturned while trying to flee a coast guard ship. Two others survived.

Taiwan, which China claims as its own territory, has complained in recent years about Chinese fishing boats and other vessels operating in Taiwan-controlled waters, especially around the Kinmen and Matsu islands that sit a short distance from China's coast.