A local Catholic rights group lodged a complaint against an official of the state intelligence agency and the prosecution on Wednesday for allegedly fabricating evidence to charge a North Korean defector with espionage.

The case of Yoo Woo-seong, a 34-year-old former civil servant for the Seoul municipal government, has raised a political storm in South Korea amid mounting suspicions that the National Intelligence Service helped the prosecution obtain fake evidence, including documents purporting to be Yoo's immigration records.

The Korean Catholic Human Rights Committee filed the complaint against Lee In-cheol, the NIS official working as a South Korean consul in China's northeastern city of Shenyang, and two prosecutors investigating the case.

"Lee obtained and handed over the document to the prosecutors despite prior knowledge that it was fabricated by another NIS employee," the committee claimed in a statement.

Yoo, previously a Chinese national in North Korea, was indicted last year on charges of handing over the personal information of more than 200 North Korean defectors to Pyongyang after disguising himself as a defector in order to enter South Korea.

After a local court acquitted Yoo of espionage, prosecutors appealed the verdict and submitted Chinese immigration records apparently showing that Yoo entered North Korea on May 27, 2006 and left through China on June 10, 2006.

At the request of a Seoul appeals court, however, the Chinese Embassy in Seoul examined the records and announced that they are fake, according to Yoo's defense lawyers.

Despite the suspicions, prosecutors at the Seoul Central District Prosecutors Office probing Yoo's case said Wednesday they will appeal the ruling

"It is not yet concluded that the evidence was fabricated," a prosecution official close to the investigation said, adding that a decision on whether to drop charges against Yoo will be made after fully looking into the immigration records.

The records were a key piece of evidence in the case since prosecutors claimed Yoo was recruited by the North's spy agency during his stay in the North and had since engaged in espionage activity. (Yonhap)