North Korean diplomats and officials stationed overseas have refused a recent government order to send their children home, a news report said Tuesday, marking an unprecedented backlash against the communist leadership.

About 4,000 children were supposed to return home by the end of last month, South Korea 's Yonhap news agency reported, citing an unnamed person well-versed in North Korean affairs. The North has delayed the deadline by a month.

Each official was allowed to keep one child at their overseas post, the report said.

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North Korean diplomats are opposed to the order mainly because of educational reasons, said Yonhap.

Pyongyang's move could result in defections by North Korean diplomats and officials, said Yonhap, adding that the refusals mark unimaginable acts of disobedience in the tightly controlled country.

Disloyalty to North Korean leader Kim Jong Il is a serious crime that can result in detention in the country's harsh political prison camps.

North Korea has dispatched Kim Chang Gyu, a vice foreign minister, to Beijing to assess the situation in China where North Korean diplomats and officials have refused to send children back to Pyongyang, reported Yonhap.

A North Korean Embassy official in Beijing said he could not confirm Kim's trip to China, and dismissed the Yonhap report as a "wrong guess." He asked not to be named as he was not authorized to speak to the media.

Complete coverage is available in FOXNews.com's North Korea Center.