According to The Herald, the local authority’s internal auditors have already filed two reports on building work carried out for its housing department.

Now they are understood to be putting the finishing touches to a third document to be presented to senior officials next week.

Sources in the local authority told The Herald that Police Scotland had not been informed of the investigation, which is at a relatively early stage and follows whistleblowing disclosures.

A Falkirk Council spokesman said: “The council has a whistleblowing policy in place along with other measures to allow concerns to be raised with the council’s corporate fraud team directly or anonymously.

“Any allegation of fraud is taken seriously and investigated by our own corporate fraud team. Such investigations can lead to a range of outcomes including making recommendations where improvements can be made to processes or controls or in more serious cases, triggering of the council’s disciplinary policy or referral to Police Scotland.”