Chinese authorities sent a message to its fishermen to respect maritime laws and abstain from resisting inspections by the Korean Coast Guard, citing crackdown measures being implemented to cope with illegal fishing, the government here said Sunday.

The Korean Coast Guard discovered the message that was sent from the marine affairs unit of China's Shandong Province to its fishermen, while questioning a Chinese fishing boat that was caught fishing off the western coast Thursday.

The message, spread via the Chinese global positioning system (GPS) Beidou, said, "The South Korean government has strengthened its control over the West Sea and has implemented an 'act first and report later' guideline for its Coast Guard."

Korea has made clear that its security forces have been authorized to use firearms and even crew-served weapons to apprehend fishing boats operating illegally within its exclusive economic zone.

The message added, "Fishing boats must stick to the law and not resort to violence," and urged Chinese seamen to "firmly stop violating the fishing policies of other countries."

The Chinese authorities' warning to its fishermen came after two incidents earlier this month, where the Coast Guard used weapons against illegal fishing.

The first incident took place Nov. 1, when the Coast Guard fired about 700 rounds from a ship-mounted M60 in the process of capturing two Chinese fishing boats operating illegally off the coast of the South Korean port city of Incheon.

The second took place Nov. 12, when the Korean patrol boats fired 95 rounds to chase off around 30 Chinese boats.

After the first incident, China called in the Korean ambassador to express strong displeasure with what it sees as a "violent" crackdown, although both confrontations caused no casualties or damage.

Illegal fishing has been a source of diplomatic tensions between the two countries in recent months. Since a Chinese vessel intentionally crashed into and sank a Korean patrol boat in October, Korea has toughened measures against illegal fishing in its waters.

The number of illegal Chinese boats reported off the West Sea has decreased after the Korean authorities beefed up their crackdown. (Yonhap)