Washington, May 9 (IANS): The wife of an American citizen detained in North Korea for suspected "hostile acts" against Pyongyang, has pleaded for his release, the media reported.

The news of his arrest came on May 7 after North Korea's state news agency announced that security services had detained Kim Hak-song "on suspicion of hostile acts against the state".

His wife, Kim Mi-ok told CNN on Monday that she waited in a Chinese border city for her husband to step off the train on May 6 from North Korea.

"I waited until the last passenger. I waited until the train doors closed, but I couldn't find him," Kim Mi-ok said.

"I was speechless, I was in shock," she said.

Kim Mi-ok said her husband had been falsely accused.

"He went to the country and served with love and I believe his words that there was nothing else," she told CNN.

Kim Hak-song is an ethnic Korean who was born in China.

He became a naturalised US citizen over a decade ago. It was here that he was also ordained as an evangelical Christian pastor affiliated with the Oriental Mission Church in Los Angeles.

According to Kim Mi-ok, Kim Hak-song had been teaching agricultural techniques at Pyongyang University for Science and Technology and did not engage in any missionary work.

In April, North Korea had detained another US citizen for alleged hostile activities and there are two other Americans serving jail terms for anti-Pyongyang activities.