Kim Kyong Hui, North Korean leader Kim Jong Un’s aunt, left for Europe after the execution in North Korea of her husband Jang Song Taek, the Japanese daily Yomiuri Shimbun reported Thursday.

An unnamed source told the Yomiuri that Kim Kyong Hui went to Switzerland after the execution of Jang in December and has since moved to Poland.

In Poland, Kim Pyong Il, step-brother of former North Korean leader Kim Jong Il – Kim Kyong Hui’s brother – has been working as diplomat since 1998.

Kim Kyong Hui’s lack of public appearances in recent months has led to widespread speculation.