President Moon Jae-in expressed his gratitude Wednesday to the governments of Gabon, Nigeria and France for cooperation in successful efforts to secure the release of a South Korean man kidnapped by pirates off the coast of Gabon in early May.

On his social media account, Moon also commended hard work by South Korean civil servants and authorities charged with handling the matter.

The previous day, the foreign ministry announced that the man in his 50s had been set free in southern Nigeria. He was among six crew members taken hostage by unidentified pirates during attacks on two Senegal flagged fishing vessels. The South Korean man and five nationals of Senegal and Indonesia were released in good health after 37 days of captivity, according to the ministry.

"Immediately after the abduction, the government put a 24-hour response system into operation and made efforts for the early return (of the hostage)," the president said.

He added South Korea had close consultations, albeit unannounced, with Gabon, Nigeria and France.

"Protecting the people's lives and safety is the first duty of the government," he stressed.

Especially, he praised officials at the foreign ministry's consular service center and local embassies.

"In addition, I deliver a message of particular gratitude to the Gabonese, Nigerian and French governments that did not spare help and cooperation for the return of our national," Moon wrote. (Yonhap)