Department of Special Investigation (DSI)is preparing to summon eight companies to provide information as witnesses in the oil hoarding case after detecting irregularities in 20 maritime oil shipments.
On 20 Apr 2026 GMT+7, reporters reported that officers from the Crime Suppression Division's Consumer Protection Unit inspected an oil depot in Ang Thong Province and found possession of large quantities of fuel oil without transport documents. They also collected oil samples for quality testing and initiated criminal proceedings under the Fuel Trade Act.
However, the Special Case Committee has resolved that criminal offenses related to fuel oil under the Fuel Trade Act, impacted by conflicts in the Middle East involving oil traders under Sections 7 or 10, regardless of registration status, that are complex or severely affect the public or industry since 1 Mar, will be accepted as special cases until the Middle East conflict subsides.
Therefore, Pol. Lt. Col. Yuttana Praedam, Director-General of the DSI, assigned the Consumer Protection Case Division, led by Pol. Lt. Col. Waranan Srilam, to coordinate with local investigators to determine if the case qualifies as a special case per the committee's resolution, and to plan joint operations. The Consumer Protection Case Division has already received investigation file 42/2569. On 17 Apr, Pol. Lt. Col. Waranan Srilam ordered Lt. Col. Phatchaphon Suphanichwaraphat and his investigative team to work with Ang Thong provincial police and energy officials to establish facts.
The involved officials and the DSI then inspected an oil company in Mueang District, Ang Thong Province, which is an oil trader under Section 10 of the Fuel Trade Act (2000). The site is also an oil depot licensed under Category 3 fuel storage by another legal entity from the Bang Khun Thian area, also an oil trader under Section 10. The depot manager led the inspection, which included reviewing transport documents, oil types, inventory volumes, customer lists, and related documents. Additionally, Ang Thong's energy office collected samples from two of five oil tanks (two tanks had previously been seized by police, with one unused tank).
The inspection results are as follows: 1. Seized Tank TD2, Diesel B7, measured 102.2 cm, holding 102,412 liters; 2. Seized Tank TS4, Gasohol 95, measured 96.8 cm, holding 140,879 liters; 3. Tank TD3 (unused), Diesel B7, measured 27 cm, holding 51,640 liters; 4. Sampled Tank TD1, Diesel B7, measured 222.3 cm, holding 291,250 liters; 5. Sampled Tank TS5, Gasohol 91, measured 40.2 cm, holding 64,997 liters. The investigative team will coordinate with the Crime Suppression Division regarding further investigation under the Special Case Investigation Act (2004).
Pol. Lt. Col. Yuttana Praedam, Director-General of the DSI, stated that regarding the transfer of the Ang Thong company case, which the DSI and partner agencies jointly investigated for fuel possession irregularities, the DSI plans to accept it as a special case as well. It will be a separate special case, distinct from case number 59/2569. The DSI does not need to wait for the provincial commerce office of Ang Thong to file charges with local police because the Crime Suppression Division has already initiated criminal investigations. The DSI is merely receiving additional details and is currently coordinating documentation.
Moreover, the DSI does not necessarily need to wait for the fuel quality test results from Ang Thong's energy office, which randomly sampled two tanks out of five, to accept the case as special. The DSI is tasked with gathering all information to present to the Director-General for consideration of any case as special. The Ang Thong company's case no longer requires submission to the Special Case Committee as it falls under the committee's 9 Apr resolution to designate certain fuel-related criminal offenses, linked to the Middle East conflict, as special cases when committed systematically or with severe public or industrial impact.
Once the DSI receives the case files transferred from the Crime Suppression Division concerning the Ang Thong company, it will begin issuing summonses to witnesses. All individuals involved will be called to provide statements to the special investigation team, even if they are not listed as authorized signatories or shareholders. The investigation will broaden to include those involved in wrongdoing or supporting offenses, not just fuel adulteration. If further tests find additional adulterated fuel tanks, the DSI will pursue additional legal action.
Pol. Lt. Col. Yuttana added that the appointment order for the special investigation team, which will integrate personnel from other agencies working with the DSI, will be proposed to the Prime Minister for signing. This process is currently progressing through the Ministry of Justice hierarchy. The special investigation team will collaborate to verify facts and efficiently resolve the oil hoarding case.
Regarding irregularities found in oil transportation by 12 vessels over 20 voyages in Surat Thani waters, owned by eight companies, which delayed shipments causing about 57 to 60 million liters of oil to disappear at sea, preliminary investigations found no involvement of refineries in the eastern region. The refineries did deliver oil to the transport vessels as scheduled.
Reports further state that the special investigation team led by the Consumer Protection Case Division has issued summonses to the eight companies owning the 12 vessels (20 voyages) to testify as witnesses at the Consumer Protection Case Division, 10th floor, Government Complex, Building C, Chaeng Watthana Road, Bangkok. Irregularities were found in 20 maritime shipments from refineries in the eastern region to oil depots in Surat Thani, where approximately 57 to 60 million liters of oil went missing at sea. The special investigation team will begin questioning the witnesses from Tuesday, 21 to 23 April. Questions will cover the companies’ business operations and the relevance of maritime oil transport documents to the shipments.