BEIJING, China — China has once again churned the choppy political waters of its regional relationships, with South Korea now up in arms after a Chinese fishing boat captain murdered a Korean coast guard officer this week.

Beijing was reticent about issuing an outright apology to South Korea. A spokesman for the Ministry of Foreign Affairs said Tuesday that it “regrets” the incident, though it didn’t acknowledge the murder charge.

“The Chinese side regrets that the relevant incident caused death of [a South Korean] coast guard officer, which is an unfortunate event,” said China's Foreign Ministry spokesman Liu Weimin.

This year has witnessed continually rising tensions between China and the many neighbors with which it shares international waters, from the South China Sea around Vietnam and the Philippines to the Yellow Sea with South Korea.

The ongoing pattern in regional relations has typically included a few weeks of calm, then an incident in which China is accused of aggressively trying to expand its reach into territorial waters outside of accepted boundaries.

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This week, the crisis came when a Chinese fisherman stabbed two South Korean coast guard commandos when they tried to arrest the fishermen for operating illegally in Korean waters. Officials say the fisherman denies having stabbed anyone.

South Korea’s Chosun Ilbo newspaper noted that this was the second murder of a South Korean sailor by Chinese fishermen over illegal fishing in the South China Sea in three years. The first drowned after an attack in 2008.

“The violence of Chinese fishermen can no longer be swept under the carpet,” the paper said in an editorial on Tuesday. “Unless Korea deals with it firmly, such acts will only increase. Strong reprisals are the best deterrent.”

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South Korea has lodged a formal protest with China’s ambassador, and China has pledged to work with South Korea and investigate the incident. South Korean officials have also seized the Chinese fishing boat and detained all nine members of the crew.

“Beijing expects Seoul to ensure the detained Chinese fishermen's legal rights and guarantee their humanitarian treatment,” the official China Daily newspaper said, quoting Foreign Ministry spokesman Liu.

Chinese fishing in South Korean waters has been an ongoing source of tension in that particular relationship for several years. Korean officials say hundreds of Chinese ships work the waters illegally, drawing down fishing stocks and reacting with increasing violence as officers attempt to enforce international boundaries. This particular boat was reportedly fishing about 50 miles off a southern South Korean island.

But it’s the very same issue that has infiltrated China’s relationship with nearly all of its sea neighbors. Both the Philippines and Vietnam have become so annoyed with growing Chinese aggression at sea that they’ve proposed renaming the South China Sea.

In the East China Sea, China has had ongoing disputes with Japan over territorial waters and island claims. The two countries reportedly agreed to work on a crisis plan to develop a framework for dealing with each other when emergency incidents arise. But China hasn’t engaged with its other sea neighbors in the same way, and for now, tensions remain inflamed.