South Korean activists say a Christian was publicly executed last month in North Korea for distributing the Bible.

The communist nation accused also accused Ri Hyon Ok, a 33-year-old woman of spying for South Korea and the U.S.

The report by anti-North Korean groups say the woman was executed in the northwestern city of Ryongchon near the border with China on June 16.

The report also claimed the woman's parents, her husband and three children were sent to a political prison camp the day after the execution. The report also showed a copy of Ri's North Korean government issued identity card.

It is impossible to verify the report about the North Korean government, since it is so secretive and tightly controls its citizens.

On Thursday, a South Korean think tank on human rights released their annual report that said the number of public executions in North Korea have dropped in recent years.  The report said executions are still carried out for crimes ranging from murder to the distribution of foreign movies.

The communist nation claims to guarantee freedom of religion for its 24 million people, but in reality severely restricts religious observances.

The government has authorized four state churches, one Catholic, two Protestant and one Russian Orthodox, but they cater to foreigners and ordinary North Koreans cannot attend.

However, defectors and activists say more than 30,000 North Koreans are believed to practice Christianity secretly.