Security firm G4S lost £50m over failings in the delivery of its contract to provide security guards to the Olympic and Paralympics Games.

This announcement comes in the company’s H1 2012 results, the day before the opening ceremony of the Paralympic Games, with G4S having told Recruiter last week that it is set to deliver on its Paralympics contract without any of the troubles that befell it pre-Olympics.

According to the results, an Olympic and Paralympic contract review is already underway and should be completed in the second half of September.

The company’s £50m loss was little more than a blip in its broader finances – when that exceptional item is excluded from results, it registered a turnover of £3.90bn for the first six months of the year, an increase of 5.8% or £273m on 2011.

Its profit before interest, taxation, amortisation, acquisition-related costs and exceptional items remained flat at £236m.

Chief executive officer Nick Buckles says: “We were deeply disappointed that we had significant issues with the London 2012 Olympics contract and are grateful to the military and the police for their support in helping us to deliver a safe and secure Games.”