North Korea executed three leaders of the underground church and jailed 20 other Christians, reported a news agency focused on Asia.
Although the execution and imprisonment happened in mid-May, news only got out this month.
According to AsiaNews, North Korean police raided a house in Kuwal-dong in Pyungsung county, Pyongan province, and arrested all 23 believers who were gathered there for religious activity.
The leaders were sentenced to death and soon after executed. The other 20 were reportedly sent to the infamous prison labor camp No. 15 in Yodok. The 23 Christians had come to faith after some of them traveled to China on business and met with church members there.
North Korea Intellectual Solidarity, a group of North Korean defectors based in Seoul that seeks to raise awareness about injustice in North Korea, confirmed the events.
For eight straight years, Open Doors has ranked North Korea as the world's worst persecutor of Christians.
In 2009, The Associated Press reported that a 33-year-old Christian woman accused of distributing Bibles and "spying" for foreign countries was publicly executed in North Korea.
There are an estimated 400,000 Christians in North Korea who live under the constant threat of imprisonment, torture or public execution if authorities discover their Christian faith.
Being a Christian in North Korea is considered one of the worst crimes by the oppressive government. All citizens are forced to adhere to a personality cult revolving around the worship of the current dictator and his deceased father.
No other religious beliefs are allowed in the country.
An estimated 40,000 to 60,000 Christians are currently in prison labor camps because of their faith.
"Please pray for believers in North Korea who follow Jesus at great risk," urged The Voice of the Martyrs Canada. "May they have opportunities to meet together and provide encouragement to one another."