South Korea lodged a complaint with China earlier this month against an increase in illegal fishing by Chinese vessels in its waters following the April 16 sinking of the ferry Sewol, which claimed more than 300 lives. The tragic accident has led South Korean maritime police to reduce surveillance on illicit operations by Chinese fishermen in the country’s exclusive economic zone.

South Korea has long been troubled by illegal fishing by Chinese boats. But it is particularly deplorable to attempt to take advantage of a neighboring country’s tragedy for personal gain. The Chinese government may well know that it does not fit the image of an emerging superpower seeking to expand its role on the global stage to let its people commit such disgraceful acts.

During their first summit in June last year, South Korean President Park Geun-hye and her Chinese counterpart Xi Jinping agreed to make the waters between the two nations a “sea of peace, cooperation and friendship.” After a lull over the ensuing months, however, Chinese boats began returning in flocks to catch fish in South Korea’s EEZ in the Yellow Sea.

Under a bilateral fisheries accord, the two sides are supposed to allow a total of 1,600 vessels from each other’s countries to haul 60,000 tons of fish in their waters each year. With fishing grounds off China’s coast increasingly polluted, a far greater number of Chinese boats have entered South Korean waters, prompting concerns that they are exhausting Korea’s marine resources and destroying the ecosystem in the sea between them.

China should turn its words on creating a sea of peace and friendship into action. The two countries need to work out more concrete and effective measures to strengthen cooperation in cracking down on illegal fishing at their annual fisheries talks in June.

South Korean maritime police, who have been under fire for their botched response to the ferry disaster, should not be discouraged from continuing their mission to prevent illegal operations by Chinese fishing vessels.