Some of South Korea's biggest names in pop traveled to Pyongyang earlier this month to stage two concerts. Photo courtesy of EPA/S.Korean Art Performance Press Corps.

SEOUL, April 9 (UPI) -- A group of North Korean teenagers were sentenced for dancing to South Korean pop music last month, Japanese media reported.

The Asahi Shimbun said Monday that six teenagers aged 16 and 17 in the North's Ryanggang Province stood public trial on March 22 for listening and dancing to roughly 50 K-Pop songs, before distributing them to others on a flash drive.


Four of them were found guilty of "anti-national" conspiracy and received a year of labor.

The sentence for the other two teenagers are unknown but all six were sent to an offenders' institution after the trial, according to the report.

In the North, those who commit less serious crimes receive a labor sentence which ranges between six and 12 months.

However, numerous North Koreans who defected to the South have said the laborers are treated "almost like forced laborers."

The trial came less than two weeks before a group of South Korean K-Pop singers and bands travelled to Pyongyang to perform in front of North Korean government officials, including leader Kim Jong Un who is said to be a fan of girl band Red Velvet.

The crowd also included young members of the ruling Workers' Party who have lived abroad or are familiar with Western music.

North Korean media reports on the two Pyongyang concerts, however, did not mention the names of the South Korean celebrities or the title of their songs.

The state-run broadcaster Korean Central Television also muted the songs when airing clips from the performance.

However, footage of both concerts have already made their way into the black market and are being distributed among North Korean citizens, DongA Ilbo reported.

Many North Koreans, who have reportedly watched the 2009 South Korean drama "Iris," were widely moved to see singer Baek Ji-young, who sang the theme song called "Don't Forget Me."

They are also said to be confused by the Red Velvet's lyrics. The girl band's songs, including "Red Flavor," were entirely removed from the North's media coverage.

Observers speculate South Korean broadcast contents were copied onto memory sticks in China for the North Korean market.

Reports say North Korean elites request South Korean media contents via the North-China border.