Seoul, South Korea (CNN) A senior North Korean military leader has been executed for "factionalism, misuse of authority and corruption," a South Korean government official with knowledge of North Korean affairs told CNN Thursday.

The official, who spoke to CNN on condition of anonymity, declined to give further details on how or when Gen. Ri Yong-gil, chief of the North Korean Army's general staff, was executed.

Ri was appointed to the position in 2013, South Korea's Yonhap news agency reported.

One source told Yonhap that Ri was executed last week.

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His execution is the latest in a string of high-profile officials that have been purged in a dramatic fashion.

Ri appears to be one of the most senior officials executed to date, according to a U.S. defense official. The official said the execution continues a brutal consolidation of power by North Korean leader Kim Jong Un.

David Kang, a professor of international relations at the University of Southern California, told CNN the move is a show of strength.

"It is another way for Kim Jong Un to show he is in power. He is still young, and still learning who is on his side and who is not," said Kang. "The people who are on the wrong side become disposable."

Heightened tensions

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North Korea insists the launch was to put a satellite into orbit, but it was viewed by other nations, such as Japan and South Korea, as a front for a ballistic missile test.

This type of rocket, analysts say, could also be used as an intercontinental ballistic missile (ICBM) and could potentially carry a nuclear warhead.

In retaliation, South Korea and the United States are taking what action they can against the North Korean regime

South Korea said Wednesday it is closing the Kaesong Industrial Complex , a joint North-South-run initiative located in North Korea and a rare of example of cooperation between the two countries.

The United States approved new sanctions to punish Pyongyang for carrying out the recent nuclear and ballistic missile tests as well as for other malicious activities, including cybersecurity attacks and human rights abuses.

And senior military leaders from the United States, South Korea and Japan held a trilateral meeting in Hawaii Wednesday, pledging to redouble intelligence sharing on the reclusive nation's nuclear and missile threat.

"The senior military leaders also agreed to coordinate further on mutual security issues to enhance peace and stability in the region," a statement from the U.S. representatives read.

Latest execution

The general is the latest in a line of disgraced officials who have been executed by Kim's regime.

In May of last year, Hyon Yong-chol, the country's defense minister, was publicly executed after the regime accused him of treason . He was reportedly killed with an anti-aircraft gun.