North Korea and South Korea exchange fire after agreeing to peace talks [VIDEO]

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North and South Korea briefly exchanged fire Wednesday along their maritime border in the Yellow Sea. The skirmish comes a month after the two countries agreed to try to restart talks.

“North Korea appears to be provoking the South in a calculated manner to highlight the need for a peace treaty to replace the armistice agreement after the war,” Kim Yong Hyun, a professor at Dongguk University in Seoul, told Bloomberg. “I doubt the North will go so far as to risk breaking down the dialogue.”

The South Korean defense minister said the three shots his country fired were in retaliation for a trio of shots fired by the North toward the Northern Limit Line (NLL), the border between the two countries, the Washington Post reports. The exchange happened not far from Yeonpyeong Island, which was shelled by the North in November 2010, killing two South Korean Marines and injuring at least six others.

The NLL, which was designated by the United Nations in 1953 and was rejected by the North, has been a source of tension and repeated conflict. However, South Korean officials seemed unperturbed by Wednesday's incident and said it wouldn't affect the recently restarted talks, Bloomberg reports.

"If we had sustained any damage or if the shots had landed near our vessel, then we would've responded immediately," a defense official told South Korean news agency Yonhap. "But the shot appeared to have fallen near the NLL, and we directed our warning shots toward the line."

A defense official said that South Korea hasn't raised its military alert level, and it was unaware of any drills planned in the area.

The Los Angeles Times notes that North Korean leader Kom Jong-il "often uses surprise to keep tensions high along the land and sea borders."

Meanwhile, South Korean news agency Yonhap reported that the North is plotting to assassinate the South's defense minister, who is known for taking a strong stance on retaliation to the North's attacks, Agence France-Presse reports – in March he told soldiers to "shoot first and report later." He has been called a "traitor" and "warmonger" in North Korean media.

An unnamed South Korean official said hitmen had been sent to Seoul to target him, although he was unsure if they were North Koreans, foreigners, or "moles working in the South." AFP says that the North has sent secret agents into South Korea before to target its defectors, but not South Korean officials. Two agents were discovered last year, pretending to be defectors in order to assassinate Hwang Jang-Yop, the highest ranking North Korean to defect to the South.

On Tuesday, the South Korean ministry that handles relations with North Korea said it had been targeted by hackers trying to attack the unification ministry's website. The hackers, which had Chinese IP addresses, planted malicious software in the e-mail account of a government aide, AFP reports. A ministry official said that attempts to hack into the network are were constant.

North Korea's government is suspected of maintaining high-level hacker units. Last year, South Korea announced an expansion of its own cyber warfare unit, claiming it needed to in order to fight the increase in attacks from the North.