The Department of Special Investigation (DSI) has traced the 'Masked Man' fuel hoarding operation using 11 ships that ran throughout March 2026 to transport fuel offshore in Surat Thani province. They found abnormalities in 24 ship voyages showing deliberate delay behavior involving about 60 million liters of fuel. The investigation into the companies owning these 11 ships is still expanding.
Regarding the case, the Special Case Committee (Board of Special Cases) unanimously accepted criminal offenses related to fuel under the law governing fuel trade, linked to the Middle East regional conflict caused by oil traders under Section 7 or Section 10, or traders regardless of legal registration, who operated in a complex or organized manner causing serious impact on the public or the industrial sector.
On 11 April 2026, reporters reported on the investigation progress of fuel hoarding. The special investigation team found key information about abnormal fuel transport offshore in Surat Thani involving 60 million liters of fuel over 24 voyages exhibiting slow or abnormal navigation routes. This 60 million liters figure is an updated amount from the National Marine Security Operations Center (NMSOC), which previously suspected about 57 million liters of missing fuel.
Looking back at earlier investigations, during March there were 20 voyages linked to the missing 57 million liters of offshore fuel in Surat Thani. Currently, the special investigation team expanded the timeline from 1 to 31 March, finding 24 voyages involved.
Therefore, the amount of fuel involved increased to 60 million liters, with behaviors indicating deliberate delay, slowing navigation, and refusal to sell fuel for undisclosed purposes. The exact amount of fuel lost within the 60 million liters must be verified by NMSOC.
Moreover, they have traced 11 ships involved so far, with further investigation ongoing. The number of ships is less than the number of voyages because one ship may have made two trips within a month. The companies owning these 11 ships are still under investigation.
Preliminary investigation shows the 11 ships are Thai-flagged and operate in the waters of Bangkok, Laem Chabang, Si Racha, and Map Ta Phut before heading south. Their pattern starts by collecting fuel from refineries located in the industrial zones of Map Ta Phut, Rayong province; Si Racha, Chonburi province; and refineries in Bangkok, then sailing to fuel storage companies in Surat Thani province.
During their sailing in territorial waters, investigators must check for any abnormalities in their routes. Normally, ships from Bangkok to Surat Thani take about 35-40 hours without adverse conditions such as monsoons affecting travel time.
However, between 20-25 March, especially on the morning of 26 March at 05:00, after the night of 25 March, the Oil Fund Management Committee (OFMC) approved a reduction in compensation rates for diesel and gasoline prices, causing retail fuel prices to jump by 6 baht per liter in one day. This was a key point prompting investigators to examine ship numbers and voyages in territorial waters during 20-25 March.
They found abnormalities with about 24 voyages from 11 ships drifting in waters during that period, extending voyage times by more than 24 hours, sometimes over 48 or even 72 hours. Normally, each ship carries 2-3 million liters of fuel. If the recorded fuel quantities at origin and destination do not match the shipping documents, it must be investigated to determine if fuel leakage occurred during transport.
Reporters further note that the special investigation team must track and verify fuel transport figures from origin, en route, to destination, especially whether involved ships followed normal routes. Shipping manifests will serve as evidence, showing if ships stopped or delayed anywhere or refueled. Relevant authorities like the NMSOC, Marine Department, Excise Department, Energy Business Department, and local fuel storage companies hold this data, which must be compared to detect irregularities.
This process requires thorough and comprehensive review by the special investigation team. Another abnormality found was a major fuel storage company in Surat Thani showing increased electricity usage after the fuel price hike, especially on 26-27 March. Similarly, fuel storage companies and gas stations in Pathum Thani, Rayong, and Samut Sakhon provinces also showed increased electricity consumption, which correlates with the operation of fuel pumps, as each pump use roughly equates to 7 baht per liter dispensed.
The investigation led by the Royal Thai Police, including Deputy Police Chief Pol. Gen. Samran Nualma and Pol. Lt. Gen. Nopasilp Poolsawat, in coordination with the DSI, Energy Business Department, and provincial commerce officials, conducted inspections on 8 April at small refineries and fuel storage companies in three provinces. Detailed data must be submitted to the special investigation team as the case involves deliberate delay and hoarding in fuel sales. Preliminary evidence of increased electricity consumption in companies in Pathum Thani from 20-25 March to 26-28 March is clear, with usage rising from under 500 kilowatts to 1,600 kilowatts. This must be compared with purchase orders; if fuel storage companies received orders but did not release fuel accordingly, it could violate the 1999 Price of Goods and Services Act, Sections 25(5)(12), 30, and 31.