Tanker Monjasa Reformer, which had 16 crew on board when it was attacked by pirates on March 25, was found by the French navy off the coast of Sao Tome and Principe.
The Danish oil tanker seized by pirates has been located in the Gulf of Guinea but a part of its crew has been kidnapped, the ship's owner Monjasa said.
When the vessel was located, "the pirates had abandoned the vessel and brought a part of the crew members with them," Monjasa said in a statement on Friday.
"The rescued crew members are all in good health and safely located in a secure environment and receiving proper attention following these dreadful events," it said.
No details were provided on the number of crew kidnapped, nor their nationalities.
"Our thoughts are with the crew members still missing and their families during this stressful period," Monjasa said, adding that it was "working closely with the local authorities" to obtain the sailors' safe return.
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The Monjasa Reformer, which had 16 crew on board when it was boarded by pirates on March 25, was found on Thursday by the French navy off the coast of Sao Tome and Principe.
The owner said there was no reported damage to the vessel or cargo.
The 135-metre-long Monjasa Reformer "experienced an emergency situation" on March 25 around 160 miles (260 kilometres) west of Port Pointe-Noire in the Republic of Congo, Monjasa said.
The shipowner added that the crew had sought refuge in the tanker's secure room or "citadel" when the pirates boarded, "in accordance with the onboard anti-piracy emergency protocol".
The vessel was "sitting idle" at the time of the incident.
The Gulf of Guinea has become a global piracy hotspot in recent years although cases have fallen there since 2021 as national authorities stepped up security efforts aided by foreign naval ships, a ccording to the U.N. Security Council.
Denmark, which has big commercial shipping interests, deployed a frigate to the gulf in 2021 to protect shipping, but the frigate was pulled back last year after the outbreak of the Ukraine war.
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