CALGARY -- The co-founder of an Alberta oil and gas company has been accused of defrauding the firm of nearly $5 million.

Police allege that between September 2007 and November 2011 the suspect created three shell companies that were set up to defraud his Calgary employer.

They say the companies were used to create fictitious invoices for supplies and services that were not genuine transactions.

"The individual that was charged was in a position of authority in the company, so anything he did within that company wasn't really questioned," Staff Sgt. Kristie Verheul of the Calgary police's economic crimes unit said Tuesday.

"The invoices ranged from $8,000 on one invoice to over $100,000 on other invoices. There were multiple invoices, approximately 91 invoices. None of the services were actually rendered."

The suspect was fired from the company, which police have declined to name, in 2011. Verheul said the firm became suspicious and conducted its own internal investigation and then contacted police in 2013.

"They completed an internal investigation which included a forensic audit of all of the accounting -- every single receipt and invoice that came through that company.

"They confirmed that suspicious activity and actually went through civil proceedings first, which is very common in these situations to regain some of the money, and then came to the Calgary Police Service to deal with the criminal allegations."

Verheul said the company was successful in recouping some of the losses. But she was unable to say how much it was able to get back.

Ian W. Fisher, 53, is charged with fraud over $5,000 and money laundering. Police say no further charges will be laid and no other suspects are involved.

Fisher was the operations manager at Arcan Resources Ltd. at the time of the offences.

Aspenleaf Energy Ltd. purchased the assets of Arcan in June of this year.

"He is a former employee of Arcan Resources. We were well aware of this situation as we went through our due diligence. The previous management team was obviously on top of it and co-operating with Calgary Police Services," said Aspenleaf CEO Bryan Gould.

"We've retained most of the Arcan staff, absent the executives, who were assisting with all of the forensic investigation prior to our involvement and we would obviously continue to fully co-operate and help Calgary Police Services."

Gould said he's been in the business world for a long time and the circumstances in the case are unusual.

"You think you've seen everything in this business, but it's a strange one. Our focus is just making sure we have appropriate business controls," said Gould. "You don't want to go to bed at night thinking this can happen in your organization."

The accused is not in custody and is scheduled to return to court Sept. 11.