Paiboon said that all officials in the project must take responsibility if the investigation found the housing scheme at Rangsit Klong 1 and at Prachin Buri were marred by corruption and land was purchased at inflated prices.

National Housing Authority (NHA) governor Pornsak Bunyodom said he had called a meeting of NHA management to discuss the allegations. He asked for reports about all details of the project.

Pornsak said the authorities insisted the NHA carry out the project transparently. The NHA hired a listed company to appraise the land prices and it checked whether the prices were appropriate.

"If we find the company reported false information, we will file a complaint with the stock market to blacklist it,'' he said.

Former NHA governor Chuanpit Chaimuanwong said the two housing projects were constructed when she was governor, but she insisted they were carried out correctly. "If the land had been bought at inflated prices, we could not have sold it at Bt420,000,'' she said.

Chuanpit defended Wattana Muangsuk - the former social development and human security minister who was implicated in the corruption allegations - saying the project had nothing to do with him. "The NHA board approved all the projects,'' she said.

She admitted some home buyers complained about the projects. "We have built between 300 to 400 projects, but some houses did not come up to standard,'' she said.