China is stepping up patrols in waters near Taiwan’s Kinmen Islands, days after two fishermen drowned while being chased by Taiwan’s coast guard, which accused the vessel of trespassing.

China Coast Guard spokesman Gan Yu said in a statement on Sunday that China Coast Guard’s Fujian unit will regularly monitor the waters off the southern coast of Xiamen City, a few kilometers from Kinmen, to strengthen maritime law enforcement.

Fishermen from Taiwan and China frequently ply the waters, which have heightened tensions as the number of Chinese vessels, including sand dredgers and fishing boats, has increased significantly in the area. Kinmen residents complained about noise and sound pollution from the boats, as well as the loss of fishing livelihoods.

Although China is quite active in the waters near Kinmen, the death of the fisherman is unusual because Kinmen is closer to China than the main island of Taiwan. China claims all self-governing Taiwan as part of its territory.

On Wednesday, Taiwan’s coast guard said two of four Chinese fishermen died after their boat capsized. Their boat was said to be fishing about a nautical mile off the Kinmen Islands, which Taiwan claims as a restricted area. Two other survivors remain in Taiwanese custody.

China strongly condemned the incident and blamed Taiwan’s ruling Democratic Progressive Party for the fishermen’s deaths. It also says there is no such thing as “restricted” waters. Taiwan said the investigation was ongoing, and the mainland commission said it was communicating with Chinese authorities.

China’s Taiwan Affairs Office vowed on Sunday to take further measures but did not clarify further details. Zhu Fenglian, spokesperson for the Taiwan Affairs Office of the State Council, said that the mainland reserves the right to take further actions and that Taiwan will bear all consequences.

Taiwan split from China during a civil war in 1949, but Beijing still considers the island of 23 million people and a high-tech economy to be Chinese territory and has been escalating threats to use force if necessary to achieve its goals.

(This story has not been edited by News18 staff and is published from Yonhap News Agency-The Associated Press)