A shadow-fleet oil tanker that had previously falsified its location to avoid detection on digital ship-tracking systems ran aground near Singapore, a stark reminder of the environmental risks that such vessels pose.

A spokesman for the Indonesian navy said the Liberty, a 23-year-old oil carrier sailing under the flag of Cameroon, ran aground on Dec. 3 and that an investigation was underway. 

The ship was carrying a cargo of oil from Venezuela, according to satellite research by TankerTrackers.com Inc. and intelligence company Kpler. Both firms said that back in October, it was spoofing — making it appear on digital tracking systems off the coast of west Africa when in reality it was collecting a cargo from the Latin American country.

The grounding, not far from Singapore, is another incident involving a tanker from a so-called dark fleet of vessels that this week was branded as a “grave concern” to global shipping by the International Maritime Organization, or IMO. Singapore’s location next to a transfer hub near Malaysia and its role as a key transit point before heading to buyers in east Asia makes it particularly exposed to the risks from such ships.  

Sanctions on the oil exports of Venezuela, Iran and Russia have led to the emergence of a huge fleet of vessels that often sail without industry-standard safety certifications and insurance, and often opaque ownership structures.

Shadow fleet ships help countries under sanctions to get their oil to buyers but have raised environmental concerns.

Missing or incorrect signals can be a safety issue. The International Maritime Organization, which publishes rules for the industry, recommends that tankers don’t turn off, or falsify, their Automatic Identification System transponders. However, it is down to individual governments to impose laws that ban the practice. 

Cameroon’s flag is the only one designated as “very high risk” on a black list published by the Paris Memorandum on Port State Control, which oversees ship inspections and promotes safety. 

Industry databases don’t provide a beneficial owner for the ship, but a firm called Skyward Management Corp., with an address in Kazakhstan, is listed as its technical manager. A call to a phone number for Skyward said the number was locked. An email to the firm wasn’t immediately returned.

When the vessel was inspected in Singapore in 2017 and 2019 it was deemed high risk and had a handful of deficiencies, another international database shows. It was then sold to new owners, and subsequent inspections in Malaysia and Indonesia didn’t identify any issues. 

The dangers posed by the dark fleet were laid bare earlier this year, when a vessel called the Pablo exploded near Malaysia. That ship also had difficult-to-trace ownership and insurance, and as a result its burning wreckage sat for months off of the country’s coastline.

The insurer of the Liberty against risks including collisions and spills is not clear. 

The tanker receives classification services from a firm called Mediterranean Shipping Register. MSR was near the bottom of a performance table of so-called Recognized Organizations published by the Paris MOU in June.