NAMA is considering placing other construction companies into receivership after it pulled the plug on one of the country's biggest builders, Bernard McNamara, the Sunday Tribune understands.

Sources say it is likely that other sizeable construction companies will suffer a similar fate to McNamara as concerns over their continuing viability mount.

Despite the company insisting that it had a viable future, Nama went ahead and appointed a receiver last Thursday and it is understood that it will act with similar ruthlessness if it feels that other bailed-out construction companies don't have futures.

It is understood that receivers can be expected to be appointed to other companies before Christmas but this move will only be taken if companies do not fully cooperate with the agency.

Meanwhile dozens of businesses employed by Michael McNamara and Company will be left with nothing by the time all debts are discharged, it is feared.

Contractors working on building sites around the country have even had their equipment locked away and will now have to make a formal application to get it back.

One firm working on a high-profile project was told if it tried to remove its materials from the site, it would be stopped by security.

Michael McNamara and Company, controlled by the high-profile developer and former Fianna Fáil politician Bernard McNamara, was placed in receivership on Thursday night.

Work on a significant number of sites around the country ground to a halt after Nama asked Farrell Grant Sparks to take over the company's operations.

Michael McNamara and Company was one of the best-known building and engineering companies in the country and was working on projects at Letterkenny Hospital, NUI Galway and the Institute of Technology in Tallaght.

Pat Harte, the owner of one of the sub-contractors working on the project at Tallaght, said that he had been contacted by the receiver late on Friday.

"We rang them numerous times and eventually they returned the call. They told us to value what we had done, list the plant and tools and so," he said.

"We know we are going to get nothing. I told them by the time the banks, Revenue and themselves get their money, there would be nothing left.

"I said we would go in and get our own plant and materials back, even if we had to dig it up. He said there was security on site and it was now his property."

Harte said that Bernard McNamara would walk away from the disaster but that this would damage the sub-contractors involved for years to come.

He said: "There will be a big hullaballoo about this for four or five days and then everyone will forget about it. McNamara will walk away and yet the small firms are crippled.

"At the end of the day, any work I did, I am liable for, there's nobody to protect me. We are not going anywhere though because failure is not an option.

"It's daylight robbery really but there is no point in codding yourself, we are not going to get our money back."

Earlier this year, Bernard McNamara – who is being pursued by his own creditors – said that the company continued to be viable.

He had stepped down as a director of the company and from his management role to ensure his personal financial difficulties would not affect the business.

McNamara is said to be "devastated" by the demise of his company.

Some estimate its downfall could result in another 1,100 jobs in construction disappearing.