A woman believed to be the ex-girlfriend of North Korean dictator Kim Jong-un has been executed by firing squad, it was reported today.

Singer Hyon Song-wol was arrested along with 11 other entertainers on August 17 on charges of pornography, according to South Korea’s largest daily newspaper Chosun Ilbo.

Three days later, the group were shot dead in front of their family members.

The arrests were over videos purportedly made by the entertainers of themselves having sex which were then sold. Some of the tapes were sold in China, Chosun Ilbo reported.

A source told the paper some of the group had Bibles in their possession, and all were treated as political dissidents.

The group were members of North Korea’s most popular music troupes Unhasu Orchestra and the Wangjaesan Light Music Band.

After the executions, family members of the victims were taken to prison camps while both music groups were disbanded.

“They were executed with machine guns while the key members of the Unhasu Orchestra, Wangjaesan Light Band and Moranbong Band as well as the families of the victims looked on,” the source told the paper.

The source added that all of the families of the executed appear to have been sent to prison camps under North Korea’s principle of guilt by association.

Kim met Hyon a decade ago before either of them were married, but his father Kim Jong-il ordered the relationship to stop, reported Chosun Ilbo.

Kim’s wife Ri Sol-ju was also a member of the Unhasu Orchestra before she married him. Hyon went on to marry a soldier.

But since then there have been rumours that Kim continued an affair with Hyon, the newspaper said.

There have been widespread hopes that Kim as a young leader is more open to international influences than his father, but evidence has yet to prove this is the case in the highly secretive state.

Chosun Ilbo quoted a source saying: “Kim Jong-un has been viciously eliminating anyone who he deems a challenge to his authority,” adding the executions “show that he is fixated on consolidating his leadership.”

It comes as a senior US envoy was due to travel to Pyongyang this week to appeal for the release of an American sentenced to 15 years’ hard labour.

Bob King’s arrival in North Korea would be the first public visit from a US administration official in more than two years.

He is hoping for a pardon and amnesty on 45-year-old Kenneth Bae, a tour operator and Christian missionary was arrested last November and accused of committing “hostile acts” against North Korea.

•Credit (except headline): London Evening Standard. •Photo shows North Korean dictator Kim Jong-un and executed ex-girlfriend, Singer Hyon Song-wol.