Thai authorities want to question dozens of people, apparently including former prime minister Thaksin Shinawatra, his family and allies, on suspicion of funding recent bloody anti-government protests.
The protests, by disgruntled supporters of self-exiled Mr Thaksin, descended into Thailand's worst political violence in living memory when troops moved in to disperse them, raising fears for the stability of the US ally.
The government has launched a reconciliation plan aimed at healing divisions between Mr Thaksin's mostly rural and urban poor supporters and the military- and royalist-linked establishment.
But it has also blamed Mr Thaksin and allies for instigating the violence and filed charges of terrorism against them.
The department of special investigation - Thailand's equivalent of the US FBI - said 69 individuals and 14 companies made unusually large and frequent financial transactions beginning in September 2009 and running through two months of protests that troops forcibly ended last month.
"This is not an arrest or an indictment," director general of the DSI, Tharit Pengdith, told reporters, referring to a list of people the authorities want to question.
"These individuals are simply suspected of unusual financial transactions and we ask for their cooperation to come and explain that since we are investigating political unrest," he said.
Authorities have not officially published the list but Mr Tharit said it was expected to be released later today.
Local media have been leaked details and have reported that the list includes Mr Thaksin, his wife and two children and many allies.
Mr Thaksin, a telecoms tycoon-turned-populist politician, was ousted in a 2006 military coup and later convicted of graft. He is widely believed to have been funding the anti-government "red shirt" protests over recent years.
He has repeatedly denied such accusations, including the funding of groups which the government has called "shadowy militants", some of whom were armed with rifles and grenades and battled security forces during the recent rallies.
The violence, in which 90 people were killed and about 2,000 wounded, scared off tourists and hurt growth, although recent data showed Southeast Asia's second biggest economy remained buoyant.
In an example of the sort of financial transaction investigators were looking into, the DSI said 4.23 billion baht ($130 million) was withdrawn from the bank accounts of Mr Thaksin's son, Panthongtae Shinawatra, over the period in question.
Critics said the government was harassing its opponents, many of whom have had their financial dealings restricted. "This is nothing more than political persecution," said Karun Hosakul, a member of parliament allied with the "red shirt" protesters and among those suspected of unusual transactions.
"The government is constantly sticking a knife into us every chance they have."
Reuters