PYONGYANG -- The Supreme Court of the Democratic People's Republic of Korea (DPRK) on Friday sentenced a US citizen to 10 years of hard labor for alleged subversion and espionage activities.

Kim Dong-chul, who was born in 1953 in Seoul and emigrated to the United States in 1972, was charged with plotting to subvert the DPRK system, slandering the supreme leadership of the country and gathering state and military secrets.

Running a trade company in Rason, a special economic zone in the DPRK, Kim started espionage in 2013 after coming into contact with several people from the Republic of Korea (ROK) who tasked him with collecting top party, state and military secrets of the DPRK, including its nuclear facilities, nuclear tests and photographs of warships at repairing factories, according to the prosecutor.

The people from whom Kim took orders included a correspondent of Donga Daily, an official with the ROK's Ministry of Unification and a professor at Seoul National University, said the prosecutor.

He was also accused of illegally buying a DPRK-made mobile phone in the capital city of Pyongyang via his local employee and providing the phone to South Korea.

Kim received donations from a Canadian church, gave them to kindergartens in Rason and took pictures of the local children accepting the donations, according to the prosecution.

He was arrested on Oct. 2, 2015 as he was receiving an SD card that contained photos of local markets in Rason and documents about the DPRK's nuclear programs from a local resident in Rason whom he had bought off, said the prosecutor.

Evidence was presented to the court including his passport, the SD card, a Nikon camera, a mobile phone he used to contact with the people from the ROK, text messages showing him receiving orders from the South Koreans, documents handed over to him when he was caught, and pictures he had taken of military vessels.

On March 25, Kim gave a press conference in Pyongyang making a confession to his crimes.

The DPRK government convicted a number of foreigners for anti-DPRK crimes in recent years, often making them publicly confess their actions before trying them in court.

In March 2016, American student Otto Frederick Warmbier was sentenced to 15 years of hard labor for taking down a political slogan from a hotel in Pyongyang.

In December 2015, the Supreme Court sentenced ROK-born Canadian pastor Hyeon Soo Lim to lifetime labor. He was charged with attempts to overthrow the DPRK government and undermine its social system under the guise of conducting religious exchanges over 18 years.

In late 2014, Pyongyang released three detained Americans, two of whom had been sentenced to hard labor of six years and 15 years respectively, for "hostile acts against the DPRK."