After the five-hour meeting in which he gave the project details and submitted related documents, Samak declined to go into detail about his testimony or whether he was confident he would be found innocent, saying he would wait for the result of the investigation.

Samak had supplied details of the project and the Cabinet had approved the purchase, the signing of the memorandum of agreement and the contract between Thailand and Austria, said Deputy Attorney General for Special Cases Nanthasak Pulsuk.

Since he gave all documents to the DSI there was no need to question him further regarding the project, he added.

"Samak's summons was about the project's general details," said Nanthasak, adding the DSI would see if there was still a need to call in former Interior minister Bhokin Bhalakula and his deputy.

The DSI would question the procurement committee and involved officials about the allegation that after receiving Cabinet approval, it had set unrealistically high prices, he said.

Committee members would be asked what criteria the prices were based on, if they were checked with the supplier beforehand, if there was any bargaining and had the procurement been conducted according to Bangkok Metropolitan administration regulations.

Nobody has been named as corrupt but the high prices had triggered suspicion and the investigation, said Nanthasak, adding the DSI would forward its findings to the National Counter Corruption Commission within this month.

The investigators, led by deputy director-general of the Special Case Investigation Department Colonel Thawee Sodsong, would call on Bangkok Governor Apirak Kosayodhin to answer questions about the case next week, an informed source said.

The procurement resulted from the transfer during Samak's administration of the fire-fighting work in the city from the police department to the Bangkok Metropolitan Administration. Since the BMA planned to increase the number of fire stations and the transfer left the fire fighters with only some old equipment, the BMA procured new engines and boats, the source said.