From 2008 to 2014, the NIS (National Intelligence Service)has found and indicted 21 spies disguised as North Korean defectors, but the Korean Center for investigative Journalism's investigation revealed there was no evidence of any spy activities for 2 of the spies indicted after 2012. This discovery led to exoneration of those two people. The KCIJ also discovered that the NIS had submitted fabricated evidence against Mr. Yoo Woo-sung to the court. After the KCIJ reported this discovery through an investigation in China, the Korean court contacted the Chinese government, which confirmed that the document was forged. The Korean prosecution indicted 4 NIS employees who were involved in the fabrication, who then, in turn, received prison sentences.