BANGKOK — The Department of Special Investigation will summon PC Siam Petroleum in Surat Thani to clarify allegations of oil hoarding, with the case potentially being designated as a special case under DSI jurisdiction, the Bangkok Post reported.

Authorities Probe Mystery Loss of 57 Million Litres of Fuel in Surat Thani

A task force led by DSI director-general Pol Maj Yutthana Praedam held an urgent meeting on Saturday to establish investigative frameworks following Prime Minister Anutin Charnvirakul’s order to collect data on oil stockpiling at storage facilities and consider special-case designation.

Centralized War Room

Since the required data is dispersed across multiple agencies — including the Royal Thai Police, Surat Thani Provincial Police, the Thai Maritime Enforcement Command Center, the Department of Energy Business and the Marine Department — a centralized war room will be established to monitor developments and consolidate intelligence.

Alleged Irregularities

Inspections conducted on Wednesday at six major oil depots in Surat Thani uncovered alleged irregularities. PC Siam Petroleum in particular was allegedly stockpiling 2 million litres of oil, with significant discrepancies in its inventory, sales and intakes during February and March identified by investigators. The company will be summoned to clarify these alleged inconsistencies, according to a source familiar with the case.

Such actions may violate the Price of Goods and Services Act, the source said. The case could proceed as a special case, though it requires approval from the DSI’s Board of Special Case due to its criminal nature. The DSI is expected to finalize and submit the case file to the board next week.

The Department of Special Investigation (DSI) will summon PC Siam Petroleum in Surat Thani and ask them to clarify allegations of oil hoarding by the company, as the case may be treated as a special case.

Listen to the story or get the full story in the 1st comment. pic.twitter.com/YflqEMrEDb

— Bangkok Post (@BangkokPostNews) April 5, 2026

Other Companies Cooperate

Meanwhile, PTT Oil and Retail Business and Caltex have cooperated with regulators in inspections of oil storage and transport in Surat Thani, reaffirming transparency and compliance. PTT said authorities examined March’s data on inflows, outflows and inventories and found operations had met required standards with no evidence of stockpiling or irregularities.

Star Fuels Marketing of Star Petroleum Refining Plc, which operates Caltex in Thailand, said its fuel management and marine transport complied with safety, quality and legal requirements.

Disappearance of 57 Million Litres

Regarding the disappearance of over 57 million litres of oil during maritime transport, authorities said at least 20 voyages have shown suspicious delays, suggesting possible offshore stockpiling. The Thai-MECC is leading that probe and will forward findings to the DSI.

Thai Government Confirms Sufficient Fuel Supplies During Songkran Holiday

The investigations come as Thailand continues to grapple with fuel shortages and rising prices, with authorities increasingly focused on uncovering hoarding and supply manipulation that may be exacerbating the crisis for consumers and businesses. For PC Siam Petroleum, the impending summons marks the next step in an investigation that could lead to criminal charges — and potentially expose a network of fuel diversion operating along Thailand’s coast.

-Thailand News (TN)