Meet the guy tracking illicit oil tankers from his rooftop

(CNN) — Some people watch Netflix in their spare time. Remy Osman tracks rusty tankers transporting illicit oil through one of the world’s busiest shipping lanes.

From the roof of his Singapore apartment building, the British expat, who works as a food and beverage salesman, documents the passage of these shadow vessels, often sanctioned by the US and other Western countries, for his growing online audience.

Shadow fleets, also known as ghost or dark fleets, are ships that use murky tactics to transport oil for pariah states like Russia, Iran and Venezuela. Oil revenues from these fleets, consisting of aging tankers with opaque ownership, have become crucial sources of funding for Russia’s war in Ukraine.

The US has cracked down on shadow fleets in recent months, seizing five sanctioned vessels as part of President Donald Trump’s pressure campaign against Venezuela and its now-ousted leader Nicolás Maduro, who was captured by US forces earlier this month.

In the waters off Singapore, the underground industry comes into public view.

The Singapore Strait is a crucial maritime shipping route connecting the Indian Ocean and the South China Sea. Roughly 100,000 ships pass through these waters each year, together carrying roughly one third of all goods traded globally.

The strait’s strategic location also makes it a hub for shadow fleets transiting between Iran, Russia and Venezuela to China, one of the world’s largest importers of sanctioned oil.

Osman has a front-row seat.

“Singapore is probably the best place on earth to see (shadow ships),” the 32-year-old said.

While ships above a certain size are required under international law to keep their automatic identification system (AIS) trackers on, shadow vessels will sometimes go dark to evade authorities. But because the Singapore Strait is so narrow, it’s practically impossible for a ship to transit safely without switching on its location tracker.

The strait is also so physically close to Singapore, a dense city home to roughly six million people, that Osman can see passing vessels and take photos or videos of them with just an iPhone.

Shadow fleet balloons

Since Russia’s invasion of Ukraine and the subsequent Western sanctions on Russian oil, the global shadow fleet has ballooned. While the deceptive tactics of the ships make them hard to track, data and analytics firm Kpler estimated the global shadow fleet comprised about 3,300 vessels in December 2025, representing about 6-7% of global crude flows.

The fleet is sustained through tactics such as fragmented ownership, rapid and repeated flag changes, manipulating location data, and shifting cargo at sea during the night or in areas with minimal oversight.

More than $100 billion worth of crude oil was moved through shadow and sanctioned fleets in 2025, according to Kpler.

Osman’s niche hobby began during the Covid-19 pandemic, when he was forced to quarantine for two weeks after moving to Singapore. He began spotting ships from his hotel room’s balcony and documenting their passage online.

It wasn’t until about a year ago that Osman shifted his focus to shadow vessels, after he noticed his audience was curious about the clandestine fleets. He says his page has exploded in recent months as shadow fleets have captured the news cycle.

One of his Instagram videos from last August has more than 2 million views.

There are several signs that a ship could be transporting illicit oil, Osman said.

He consults ship tracking apps and looks for older (20- to 25-year-old) ships that are operating under flags belonging to nations with lax oversight, such as Guinea, Comoros, the Gambia, and Mozambique. Sometimes a ship will outright fly the flag of Iran or Russia, making no effort to obscure itself, Osman said.

Once a vessel has piqued his interest, Osman will look up its registration number and cross-reference it against lists of sanctioned ships.

Where the vessel is sitting in the water also gives clues about where it might be headed, Osman said. A ship that is high in the water is likely not carrying much oil, while a deeper ship is likely to be carrying more crude.

Last week the US seized the Russian-flagged oil tanker Bella 1 in the North Atlantic following an 18-day pursuit which began when the tanker dodged the US Coast Guard while it was heading to Venezuela to pick up oil.

The Bella 1, which was sanctioned by the US in 2024 for transporting illicit Iranian oil, was initially operating under a Guyanese flag but the crew hastily painted a Russian flag on the tanker’s hull once the US was on its tail.

The US has vowed to enforce its embargo on shadow-fleet ships illegally transporting oil – including by seizing ships that are evading sanctions.

Meanwhile, other countries are becoming increasingly concerned about the safety threats posed by large vessels that hide their presence in busy shipping channels.

In 2024, the UK launched a “call to action” urging coastal, port and flag states to uphold maritime rules, gathering signatures from 50 countries.

The country’s Foreign Secretary Yvette Cooper told the BBC this week that the UK is ready to work with European partners to “tighten the chokehold” on the shadow fleet and adopt “a much more assertive and robust approach.”

Quickest route from East Asia to Middle East

That many of these ships are passing through the Singapore Strait is “purely a geography question,” said Jennifer Parker, a former naval officer and non-resident fellow at Australia’s Lowy Institute. The waterway is the fastest route for ships sailing between East Asia and the Middle East.

The strait also serves as an ideal stopping point between sanctioned oil-producing countries and China, Parker said.

The waters off Singapore, Malaysia and Indonesia are a hotspot for ship-to-ship (STS) transfers of blacklisted oil, according to analysts.

But because the Singapore Strait is considered an international waterway, it is not under Singaporean jurisdiction and authorities have limited options to intervene, Parker said. It is generally against international law for a country other than the flag state to board a ship, unless they can prove that the flag is false, she added.

“If those vessels were to go into Singapore, then it could take action. But going through the international strait, there are limited things that Singapore can do,” Parker said.

In a statement to CNN, the Maritime and Port Authority (MPA) of Singapore said it “closely monitors vessel movements and ‘dark fleet’ associated behaviours in the areas in its purview” and reports violations to the International Maritime Organization.

However, the MPA also acknowledged its limited capacity to act under international law.

“The Straits of Malacca and Singapore (SOMS) are Straits Used for International Navigation, where vessels enjoy the right of transit passage under the United Nations Convention on the Law of the Sea (UNCLOS),” the MPA said. The Malacca Strait, between Indonesia and Malaysia, connects to the Singapore Strait in the West.

“As these Straits form essential global shipping routes that must remain open to international navigation, this right of transit passage cannot be suspended under UNCLOS.”

On the day Osman spoke to CNN, he filmed a selfie video looking out over Singapore’s towering residential buildings towards the blurry strait far off in the distance.

“I’ve come to the rooftop to try to spot a sanctioned shadow fleet tanker,” Osman said in the video. “The ship I’m trying to spot is called Sahara. It’s sailing under the flag of Guinea at the moment, and it’s a sanctioned vessel.”

In another video filmed using a camera with a zoom lens, Osman pointed out what he said was the Sahara, peeking out from behind high-rise buildings.

Data from Marine Traffic showed the Sahara passed through the Strait Wednesday. Sahara is sanctioned by the US, the UK, Canada and Ukraine for its ties to Russia.

“It’s fascinating to connect what’s happening in global affairs to what I can see outside,” Osman said.

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