SEOUL, South Korea - A South Korean prosecutor says officials have arrested five South Koreans on suspicions of spying for the Democratic People's Republic of Korea (DPRK) .

Prosecutor Lee Jin-han said Monday the five are suspected of forming an underground organization to supply military secrets and other information to DPRK's so-called "225" spy department.

Lee said a 48-year-old South Korean businessman surnamed Kim met with DPRK agents a number of times since the mid-1990s. Two of the others arrested were former political party members.

Lee would not divulge more about the suspects.

Conviction under South Korea's National Security Law can be punishable by death.

Lee said prosecutors are investigating other South Koreans who may have aided the suspected espionage.