A “corruption dossier” has been handed to police after a council probe claims to have uncovered a procurement black hole running to more than £1 million.

Investigators said they uncovered “serious cases of non-compliance and malpractice” at Cordia, a former Glasgow City Council arm’s-length council body, set up more than a decade ago.

Officials say Cordia, which provided services including home care, was routinely overpaying on contracts with private suppliers that had not been reviewed for years.

In some cases the cost is understood to be 25 per cent more than could have been obtained through a Scottish-wide procurement system.

The investigators warned that unnamed individuals at Cordia had “overridden normal management controls”.

Their findings, which have been shared with the national Audit Scotland as well Police Scotland, are just the latest to raise questions about council procurement across the Central Belt.

The new revelations come months after Glasgow’s SNP administration finally brought Cordia, back “in house” under full council control.

The results of a full investigation were heard in secret by councillors earlier this year. However, headline findings and recommendations were made public yesterday.

A council spokesman said: “The council’s internal audit team launched an investigation into alleged wrong-doing at Cordia in May 2017.

“Allegations, which centred on procurement and contractual matters - and included claims that individuals had overridden normal management controls over a number of years, were made through the council’s whistleblowing process.

“A report on the investigation, which detailed serious cases of non-compliance and malpractice, went to the council’s Finance and Audit Scrutiny Committee in April this year and has now been highlighted in the head of audit’s Annual Governance Statement.

“Officers have shared their findings with relevant third parties, including Audit Scotland and Police Scotland.”

Council sources said it was difficult to quantify the potential cost to the public purse if the dossier’s findings are correct, over what may have been a substantial number years, but feared it may run into seven figures.

Officials have flagged up their investigation to the police in case it is of interest to law enforcement. A city council spokesman added: “Where investigations uncover information that may be of interest to other public bodies, whether that means other councils or police, we share that with them whenever we can.”

The Herald understands auditors looked in to concerns about corporate hospitality and gifts involving contractors and about council officers doing work for outside charities on the local authority’s time.

The full, secret report, sources said, could not be released because it named individual employees and contractors - and its publication would breach privacy rules.

A number of senior staff have left Cordia. Asked about this, a council spokesman said: “We don’t comment on individual staffing matters.”

The full unpublished audit investigation allegations, meanwhile, were so serious that they sparked a review of policy to be formally announced by the council’s head of audit and inspection, Duncan Black, in an Annual Governance Statement published on Friday.

Measures include:

• A relaunch of the council’s Whistleblowing Policy;

• A review of the governance documentation relating to Registers of Interest and Gifts and Hospitality;

* A new programme of Internal Audit spot checking for compliance covering declaration of gifts and hospitality and procurement matters.