In the South China Sea, China has just sent a patrol ship to protect Chinese fishermen's interests. That's after Manila refused to withdraw its vessels from China's territorial waters.

It may be just a fishery patrol boat, but it's certainly no stranger to high profile tasks. Already a veteran in escort missions near the Diaoyu Island among others, Yuzheng 310 is now on its way to the South China Sea. It's charged with safeguarding Chinese fishermen's interests in the area.

The move comes after alleged harassment of 12 Chinese fishing boats by a Philippine warship near the Huangyan Island. This later evolved into a naval stand-off. In response, China has reiterated its sovereignty over the island and warned the Philippines against further escalation.

Liu Weimin, spokesman of Foreign Affairs Ministry, said, "The UN Convention on the Law of the Sea allows coastal nations to establish a 200 nautical mile exclusive economic zone. But that doesn't give any nation the right to encroach upon other nations' sovereignty."

Already a veteran in escort missions near the Diaoyu Island among others, Yuzheng 310 is now on its way to the South China Sea.?

Despite Chinese hopes to resolve the issue bilaterally, Manila wants to take the issue to the International Tribunal for the Law of the Sea.

Of the 12 Chinese fishing boats involved, so far only 2 have returned to their base in China's island province of Hainan. Chen Minghai was onboard one of them when Philippine soldiers stopped their vessel.

Chen Minghai, a fisherman, said, "They were all carrying sub machine guns. They conducted searches on our ships and took photographs."

Chinese maritime authorities say that in recent years, China has stepped up patrols in the South China Sea. This is a response to frequent harassment of Chinese fishermen operating in the area.