A Singapore-registered oil tanker was boarded by "unidentified persons" about 300 nautical miles (555 km) off Ivory Coast in the Gulf of Guinea on Monday, the city-state's authorities said on Tuesday night.
The Maritime and Port Authority of Singapore (MPA) said that the tanker Success 9 had 20 crew onboard of various nationalities, and one of them was Singaporean.
The MPA said it was working closely with the ship owner, the Monrovia Regional Maritime Rescue Coordination Centre and the Information Fusion Centre at the Changi Command and Control Centre to monitor the situation and render the necessary assistance.
No further details were given, including the nationalities of the other crew members.
An Ivorian security source involved in the matter said a patrol boat had been sent out to rescue the tanker, but was unable to locate it because its beacon had been turned off.
"We think it's an act of piracy because the modus operandi is the same," the source, who did not wish to be named, told Reuters.
"We have sought external help from Spain and from Europe," the source added.
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, according to the U.N. Security Council.
Pirates hijacked a Danish-owned ship off the Republic of Congo last month and kidnapped some of the crew before abandoning the vessel.
(Reporting by Xinghui Kok; Additional reporting by Ange Aboa in Abidjan; Editing by Jonathan Oatis, Sofia Christensen and Jamie Freed)
