G4S is facing new allegations of fraud and overcharging following claims in court by an employee whistle-blower.

Court proceedings detailed by the Financial Times have revealed allegations of overcharging by and insider trading.

Ex-employee Malcom Batki, who had lost his unfair dismissal case alleged in court that G4S had used internal charging to hide the extent of profits from government contracts while negotiating further business. He also claimed that G4S chief executive Nick Buckles engaged in insider trading.

The claims are now being investigated by the Serious Fraud Office according to FT sources.

G4S said that it was taking the claims “very seriously”, while Mr Buckles denied that any illegality had occurred.

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