Sources in the government of South Korea have said that the North “imported a Soviet-era Golf-class diesel submarine and modified it”. Subs of this series are also known as ‘Project 629’. They are powered with a hybrid diesel-electric engine and are able to carry ballistic missiles and/or Scud missiles. Golf-class subs had been in Soviet service in 1958-1990 and were decommissioned thereafter.
Described as “ancient marine technology” in a report by the International Strategy and Assessment Center, these subs may pose serious danger to the South, Japan and the US forces in the region. It is alleged that several of Golf-class subs were purchased from Russia in 1993 by foreign entities.