The Polish foreign ministry said it had appointed a crisis team "to coordinate efforts" in contact with the owner of the Tonsberg ship and the governments of several African countries.
According to some reports, the ship’s crew consisted of Polish, Ukrainian and Filipino nationals.
The pirates are said to have boarded the ship. One crew member who escaped kidnapping is believed to have been wounded during the attack.
According to the International Maritime Bureau, all but five of the 135 sailors who were victims of kidnappings last year were abducted in the Gulf of Guinea.
(mk/gs)