SEOUL - North Korea's army chief of staff has been executed, South Korean media reported Wednesday, in what would amount to the latest in a series of purges and executions of top officials by leader Kim Jong-Un.

Ri Yong-Gil, Chief of the Korean People's Army (KPA) General Staff was executed earlier this month for forming a political faction and corruption, Yonhap news agency said, citing a source familiar with North Korean affairs.

The report came at a time of highly elevated tensions on the divided Korean peninsula following the North's recent nuclear test and long-range rocket launch.

Ri was often seen accompanying Kim Jong-Un on inspection tours, but his name was conspicuously missing from state media reports of a recent major party meeting and celebrations over Sunday's rocket launch. "The execution... suggests that Kim Jong-Un still feels insecure about his grip on the country's powerful military," Yonhap quoted the source as saying. "It shows that Kim's reign of terror still persists," the source was quoted as saying. The National Intelligence Service (NIS) in Seoul declined to comment on the report.

North Korea's recently launched satellite has achieved stable orbit but is not believed to have transmitted data back to Earth, US sources said of a launch that has so far failed to convince experts that Pyongyang has significantly advanced its rocket technology.

Sunday's launch of what North Korea said was an earth observation satellite angered the country's neighbors and the United States, which called it a missile test.

It followed Pyongyang's fourth nuclear test in January. "It's in a stable orbit now. They got the tumbling under control," a US official has said. That is unlike the North's previous satellite, launched in 2012, which never stabilized, the official said. However, the new satellite was not thought to be transmitting, another source added. US President Barack Obama spoke with the leaders of South Korea and Japan by phone on Monday night and reassured them of Washington's support, while also calling for a strong international response to the launch, the White House said.

Obama will also address North Korea's "provocations" when he hosts the leaders of the Association of Southeast Asian Nations in California early next week, aides said.

Meanwhile, South Korea on Wednesday announced the total shutdown of a jointly run industrial park in North Korea, saying Pyongyang had been using it to fund its nuclear weapons programmes.

As well as depriving the cash-strapped North of a much-needed source of hard currency, the move was a powerful message of intent in response to the North's nuclear test last month and Sunday's long-range rocket launch.

During more than a decade of operations at the Kaesong estate, Seoul has never before shut it down - despite numerous provocations, ranging from nuclear tests to the shelling of a South Korean border island.

Moreover, Japan announced fresh sanctions against North Korea on Wednesday for its latest rocket launch, including a total ban on shipping from the country and barring Pyongyang's nationals from entering.

Japan's announcement comes after the UN Security Council strongly condemned Sunday's rocket launch and agreed to move quickly to impose new sanctions of its own. "We have decided to take firm sanction steps," Japanese Prime Minister Shinzo Abe told reporters of the latest move, which adds to measures Japan already has in place over past North Korean nuclear and missile tests.

Meanwhile, Moscow on Wednesday warned that Washington's deployment of a US missile defence system to South Korea could spark an arms race in the region.

South Korean and US defence officials said last week they would begin formal talks on the deployment of the Terminal High Altitude Area Defence System (THAAD) system in response to North Korea's recent nuclear and missile tests. "The appearance of elements of the US global missile defence system in the region - which is characterised by a very difficult security situation - can provoke an arms race in Northeast Asia and complicate the resolution of the nuclear problem on the Korean peninsula," said the Russian foreign ministry.

"On a more global scale, this step can increase the destructive influence of the US global missile defence system on international security and stability."

The foreign ministry reiterated that Pyongyang's nuclear and missile tests "could not but inspire strong condemnation" but accused Washington of using them to expand its missile defence system.

The US insists that the defence system is a deterrent necessitated by the North's advancing ballistic missile programme.

China has also argued it would undermine stability in the delicately balanced region.

Pyongyang has said that the deployment of a missile defence system would be a Cold War tactic to "contain" China and Russia.

The THAAD system, in service since 2008, includes truck-mounted launchers, radars, interceptor missiles and global communications links.

Five THAAD batteries are currently operational, according to the Pentagon's Missile Defence Agency, and two more were ordered in 2014.

North Korea's rocket launch last week, widely seen as a disguised long-range missile test, sparked international fury and prompted an agreement at the UN Security Council to slap new sanctions against the increasingly defiant state.

The launch, which violated multiple UN resolutions, came just weeks after Pyongyang carried out its fourth nuclear test.