A U.S. citizen detained in North Korea has been sentenced to 10 years of hard labor for the crime of espionage, the  Xinhua news agency reported on Friday.

Kim Dong-chul, a South Korea-born pastor from Fairfax, Virginia, admitted to spying for South Korea in January during an interview with CNN in Pyongyang.

He said that he had collected pictures and files on USBs “for South Korean conservative elements” for the purpose of “destroying the North Korean system.” His said he had smuggled the materials from April 2013 to October 2015, when he was arrested.

A North Korean soldier who had access