In an announcement to the stock market this morning, the company said the investigation relates to “the timeliness of a profit warning announced by the company on 19 September 2016 and the manner of preparation and content of the company’s financial information, position and results for the period ending 31 March 2016”.

In September, shares in Mitie tumbled after the firm warned that full-year profits would come in “materially below” expectations as uncertainty caused by the EU referendum was driving clients to renew or extend larger contracts with existing suppliers and to defer investment decisions.

Mitie also blamed lower UK growth rates, changes to labour laws and public sector spending cuts for the profit warning.

Weeks later it was revealed that Ruby McGregor-Smith is to step down as a director and chief executive to be replaced by former British Gas boss Phil Bentley.

Then in November the firm issued its second profit warning in two months as it faced fresh hits from economic uncertainty and rising staff costs.

The UK’s accountancy watchdog, the Financial Reporting Council, opened a separate investigation at the end of July into Deloitte’s auditing of Mitie’s accounts for the years ending 31 March 2015 and 2016.

Mitie added: “The company is fully cooperating with the FCA but does not intend to update the market until completion of the investigation.”