A South Korean national kidnapped off the coast of Gabon last month has been released unharmed, Seoul's foreign ministry said Tuesday.

The man in his 50s was among six crew members abducted after unidentified pirates attacked two Senegal-flagged fishing boats near the Gabonese capital of Libreville in West Africa in early May.

He was freed on Monday evening (Gabon time), along with the five others of Indonesian and Senegalese nationalities, and they are all in good health, the ministry said. The shipping firm has reportedly paid a ransom.

The South Korean remains in a secure place offered by the South Korean mission in Nigeria and should be able to return home as early as this week when a flight is arranged, the ministry added.

His family has also been informed of his release.

"We are fortunate that the kidnapping incident was resolved safely, especially thanks to the family who has trusted and supported the government and the shipping company with strong patience," a ministry official said.  

A total of 18 crewmen had been aboard two ships when the pirates attacked them and forced the vessels to travel further north to Corisco, an island that belongs to Equatorial Guinea. The pirates then took off on a speedboat with only the six of them while releasing the rest.

The ministry had been working with the governments of other countries, such as France and the United States, to track down the kidnappers and locate their whereabouts. (Yonhap)