A South Korean coastguard officer was stabbed to death and another was injured in a struggle with Chinese sailors who were being detained for illegal fishing, a coastguard spokesman said. It was the second time in less than four years that a coastguard officer has died, amid increasingly violent clashes in the rich fishing grounds of the Yellow Sea between the two countries. Monday\'s 41-year-old victim was rushed by helicopter to hospital in the city of Incheon, west of Seoul, but died of organ failure. The coastguard said it started an operation early Monday to seize two Chinese fishing boats 85 kilometres (53 miles) off Socheong island, and managed to take control of a 66-tonne boat. But the other boat suddenly rammed the seized vessel, prompting nine Chinese fishermen on board to start attacking officers. It said the 41-year-old surnamed Lee, who was searching the steering room, was stabbed in the side by a Chinese fisherman with a piece of glass and a 33-year-old officer was also stabbed. The coastguard said the pair, along with the Chinese skipper, were taken by helicopter to hospital but Lee could not be saved. The 66-tonne boat and nine crew were being brought to Incheon. Illegal fishing by Chinese vessels is common in South Korean waters, with 475 boats seized so far this year compared with 370 in the whole of last year, according to official figures. In October the coastguard said it used tear gas and rubber bullets to subdue Chinese fishermen wielding clubs and shovels. Some 21 Chinese were detained but later released after paying a fine. In December 2010 a Chinese boat overturned and sank in the Yellow Sea after ramming a South Korean coastguard vessel. Two Chinese crewmen were killed. Three Chinese detained after that incident were freed following protests from Beijing. In September 2008 a South Korean officer drowned while trying to inspect a Chinese boat.