Authorities are expanding their probe into questionable practices in the national cassava-pledging scheme after finding 60,000 tonnes of the crops caught fire or suspiciously disappeared from warehouses in five provinces.
The Public Warehouse Organisation (PWO), which contracted a private company to keep the tapioca, is planning a random check in underground storehouses across the country, especially in the North and Northeast, to find whether they are involved in improprieties that have already led to huge losses.
An initial estimate found the lost and burned cassava was worth 4.1 billion baht, or nearly half of the 10 billion baht cost of the subsidy scheme, said Pol Col Korawat Panprapakorn, Department of Special Investigation's (DSI) chief of Bureau of Special Operations.
The DSI is working with the PWO to investigate the scheme in Kanchanaburi, Ayutthaya, Lop Buri, Ratchaburi and Saraburi, where 60,000 tonnes of cassava were damaged or went missing.
"We have found tapioca went missing from another 70 warehouses in other provinces," Pol Col Korawat said. "However, we have not yet identified companies which kept them."
While the PWO has been looking into the scandal, it is not an investigative unit and has not been able to turn up evidence of mismanagement or corruption within Kasetphuetpol Intertrade Co, which was contracted to store the crops during Yingluck Shinawatra's administration.
The DSI is now thinking about designating the cassava-pledging scandal as a special case, giving the department latitude to probe the company to determine how thousands of tonnes of crops could catch fire or disappear without a trace.
The scandal has raised suspicions of arson and surreptitious sale of the crops.
"We have to focus on financial damage and suspected robberies of the crops for sale," Pol Col Korawat said.
He said the DSI plans to expand its searches into other regions to identify individuals suspected of dishonest actions if its Special Case Committee determines it can act.
Their targets won't only be businessmen but also state officials whom the DSI determined may have taken part in the scam.
The cassava-pledging scheme is a carbon copy of the rice-pledging scheme in which the government promised a fixed, above-market rate for farmers to help them cope with low crop prices.
But an inspection of warehouses in the five provinces last month raised concerns over flaws in the scheme.
The disappearance of cassava, and damage to some cassava, which is used to make tapioca and ethanol, involve crops harvested during the 2011-2012 and 2012-2013 seasons, officials said.
The greatest loss occurred in two godowns in Ratchaburi, where more than 14 million kilogrammes of cassava went missing, and one of the warehouses caught on fire.
Fire was also the cause of damage in a godown that kept 8,600 tonnes in Lop Buri. An inspection of that site found the crops were also mixed with chaff.
In the same province, 1,400 tonnes of tapioca also disappeared from another warehouse.
Similar stock disappearances were also uncovered in Ayutthaya, Saraburi and Kanchanaburi where 13 million kilogrammes, 6 million kilogrammes and 11 million kilogrammes of tapioca were kept, respectively.
Officials estimated the damages at warehouses in those five provinces alone to be about 428 million baht.
While the case has caught DSI's attention, Pol Col Korawat admitted it's difficult to identify exactly the cause of the fires and stock disappearances because of a lack of evidence.
Officials can only make assumptions. One is that the warehouses were set ablaze intentionally. Another theory is that fire was sparked by a chemical reaction that can occur under piles of decaying tapioca, he said.
The second is possible because investigators found the cassava at the godowns in the five provinces were not well kept, even though the agreement between the PWO and Kasetphuetpol Intertrade Co requires the company to turn their piles over every two months to prevent overheating beneath the crops.
The DSI official said forensic experts can tell the difference between arson and chemical reaction, but it is already too late — the evidence is long gone.
"The evidence was all destroyed because it happened two years ago," Pol Col Korawat said. "We have to cut this out of the investigation."