Norwich Union has uncovered employee fraud believed to run into millions of pounds, according to reports.
Last night Norwich Union confirmed it had started civil proceedings against several workers to recover money.
Norwich Union has applied to have one female employee's assets frozen after she admitted defrauding the company of £1.5m.
According to a report in today's Times newspaper, the police have been notified of the legal action.
The insurer would not confirm or deny the specific figures involved.
A spokeswoman for Norwich Union said: "We have issued civil proceedings against a number of people following an investigation into suspected fraud.
"The police have been informed but we cannot comment any further as the case is pending. However, no policyholders have been affected by the suspected fraud."
The writ was lodged with the High Court on 28 May.
