MV NS Concord is Russian owned, Liberian-flagged oil tanker that gained notoriety in 2014 after it was allegedly connected to the submarine search in the Stockholm archipelago. The oil tanker arrived in the area on October 4 but was later charted as zigzagging across the seas, as if searching for something. The vessel "could be a mothership for a possible submarine," according to Stefan Ring, an expert on military strategies at The Swedish National Defence College. "It is possible to use a ship like this as a mothership for mini submarines. Sailing under another flag could be to hide what they really are doing," Ring said. However, Anders Nordin at the Swedish Coastguard told news agency TT that the NS Concord's movements were consistent with normal tanker movements.