(Bloomberg) -- An oil tanker was attacked on Sunday in West Africa’s Gulf of Guinea and most of its crew were kidnapped, the latest in a string of incidents highlighting the security risks to shipping in the region.

The vessel -- an oil products tanker named Duke, hauling fuel oil -- was attacked and boarded while sailing from Angola to Togo at 7 a.m. London time on Sunday, its owner, Union Maritime Ltd. said in a statement. One crew member remained on the ship, while the rest were reported missing, the International Maritime Bureau’s piracy-reporting center said in a separate notice.

Acts of piracy on shipping in West Africa have been steadily increasing in recent weeks. Earlier this month 19 sailors were kidnapped from a supertanker off the coast of Nigeria, and four crew members were taken from a smaller Greek tanker docked at a port in Togo in early November.

About 82% of crew kidnappings globally take place in the Gulf of Guinea, according to the IMB. The region remains a hotspot despite a worldwide decline in piracy in the first nine months of the year, compared with the same period in 2018. Passing ships have been advised to stay at least 200 nautical miles from the Gulf’s coast and preferably 250 nautical miles away, the Bureau said Monday.

Union Maritime said it is currently focused on the safety of its crew and didn’t plan to comment further on the incident for the time being. V.Ships, which manages the crew, said the vessel had 21 personnel on board, including 20 from India who were abducted and one Nigerian national who was left on it.

To contact the reporters on this story: Olivia Konotey-Ahulu in London at okonoteyahul@bloomberg.net;Prejula Prem in London at pprem1@bloomberg.net;Alex Longley in London at alongley@bloomberg.net

To contact the editors responsible for this story: Alaric Nightingale at anightingal1@bloomberg.net, Brian Wingfield, Helen Robertson

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