North Korea says 4 South Koreans illegally enter the North

SEOUL, South Korea — North Korea says four South Koreans are under investigation for illegally entering the country.
The North's official Korean Central News Agency said Friday that authorities "recently detained four South Koreans who illegally entered" North Korea.
The brief dispatch did not give any further details.
The announcement came weeks after North Korea freed an American missionary detained for illegally crossing its border on Christmas Day.