A family of North Korean defectors has filed a suit against the South Korean government, saying they were illegally investigated by the state intelligence agency, a liberal civic group said Wednesday.

The husband, identified only by his surname Ji, his ex-wife and two sons filed the suit with the Seoul Central District Court, seeking a total of 218 million won ($195,000) in compensation.

Ji and his ex-wife, identified only by her surname Pae, said they were unlawfully investigated by the National Intelligence Service (NIS) for more than six months after they arrived here in

2013 until they were moved to a resettlement facility called Hanawon.

All North Korean defectors have to undergo questioning for about six months by the NIS over why and how they came to the South.

The plaintiffs claimed that they were forced to make a false confession that they conducted espionage activities and sent money to the North Korean regime by selling illegal drugs in China before coming to Seoul.

Their two sons, who had already settled in South Korea by then, also suffered mental anguish as they were prohibited from meeting their parents, said the civic group Mindle 21.

Following the agency's probe, the Ministry of Unification decided not to grant the two defectors the customary financial assistance, making it more difficult for them to settle in the country.

"The plaintiffs were deprived of any contacts with the outside world, and not allowed to speak to an attorney," said lawyer Jang Kyung-uk, representing the defectors. "The ministry's decision, which was made based on the illegally conducted probe, should be nullified." (Yonhap)