A group of Chiang Mai residents holds a traditional rite ‘to ward off evil’ yesterday near the northern centre’s old city wall. One participant wore a mask bearing the likeness of anti-government campaigner Sondhi Limthongkul.

Caretaker Prime Minister Thaksin Shinawatra yesterday ruled out the possibility that judges, businessmen and bank officials took kickbacks from the procurement of CTX scanners for Suvarnabhumi Airport.

Thaksin's comments followed accusations on Sunday from the Democrat Party that his government was covering up the results of a US Justice Department investigation that allegedly includes documents with the names of people and companies said to have received kickbacks in the deal.

The Democrats alleged the Department of Special Investigation had also found that Patriot Business Consultants received Bt643 million in six payments from ITO Consortium.

The Bt643-million transaction went through a series of people, including senior judges, businessmen and bank officials, even though they were not involved in the purchase of the scanners.

Thaksin said he had not received the investigative report from the DSI and had not heard about the findings. "Actually this issue should not involve judges because it has not gone to the court,'' he said.

DSI director-general Sombat Amornwiwat yesterday dismissed reports that Worapoj Yasadatt, chief executive of Patriot Business, transferred money to senior judges, businessmen and bankers. Sombat said there were no irregularities in the transfer of the money as it was for a land purchase. The DSI investigation has not found any evidence that politicians or airport officials received benefits from Worapoj.

Sombat denied his department was covering up the investigation. He said the department had not completed its investigation and was waiting for a reply from the US, which the Office of the Attorney-General had just received.

Democrat leader Abhisit Vejjajiva said if Thaksin failed to take legal action against those found to have been involved in the CTX corruption scandal, the party would file a complaint of dereliction of duty against him. His party would also make sure that the OAG took action on the case, Abhisit said.

Democrat Party executive Kiat Sittheeamorn, an expert in international trade, said he would today disclose documents from the US Justice Department about the alleged kickbacks.

Deputy Attorney-General Thaweesak Worapiwut admitted yesterday the OAG had received the documents that the Royal Thai Police and the Anti-Money Laundering Office requested from the US Justice Department.

Thaweesak said he did not know the details of the documents. The office is waiting for the Royal Thai Police to convene a meeting to probe those suspected of taking kickbacks, he said.

A source said only those who had filed complaints over the CTX corruption scandal were questioned, including former Democrat Party MP Suwaroj Palang and People's Alliance for Democracy coordinator Suriyasai Katasila. Police will soon summon Worapoj for questioning.