The official Korean Central News Agency said on Tuesday the Democratic People's Republic of Korea (DPRK) had detained an American who illegally entered the country.

The American slipped into the country from China on Thursday and is now under investigation by "a relevant organ", the news agency said in a brief dispatch.

The detained American was believed to be 28-year-old human rights activist Robert Park, who is a Korean descent.

Park's crossing comes just months after the DPRK freed two US journalists who had been arrested in March and sentenced to 12 years of hard labor.