The MPA earlier said there were 20 crew of various nationalities onboard the vessel, including one Singapore national.
"MPA is working closely with the shipowner, 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," it said.
Reports said the 2003-built tanker is managed by Fortune Ship Management Pte Ltd — a part of the Singapore-bunkering company and shipowner, Hai Soon Group — and owned by HS Ocean Pte Ltd.
Praesidium International, an Italian private security firm, said in an update that the tanker was reported as boarded by an "unknown number of people" around 300 nm south of Abidjan, a coastal city in Côte d’Ivoire.
The report noted that the vessel could have been targeted for oil theft as it is involved in bunkering operations in the area.