IMO has used its navigational warning system to advise of an experimental communications satellite launch by the Democratic People?s Republic of Korea (DPRK). In a letter sent to IMO on 11th March 2009, the Maritime Administration of the DPRK said that the launch would take place between 4th and 8th April between the hours of 0200 and 0700 (UTC). The letter also identified the co-ordinates of two potential dangerous areas (see below), in the Sea of Japan and the Northern Pacific Ocean, which ships should avoid during those times.