The fire, which started on 29 December and required six fire engines, two aerial ladder platforms and at its peak some 50 firefighters to bring under control, gutted Arden's two storey building, destroying the site and all equipment.

It was reported to Leicestershire Fire and Rescue Service just before 3pm on 29 December as "post bags on fire in the open" although the fire rapidly spread and by the time firefighters were on the scene it was established in all areas of the factory.

A Leicestershire Police spokesperson told local newspaper the Hinckley Times that the fire was being treated as suspicious as it "may have been started deliberately". Police investigations were described as ongoing although no arrests have been made.

Alan Stockwell, managing director of Arden Direct, told the paper that a group of children had been playing in a yard near the building "20 minutes before the building caught fire".

He added: "The whole building has been destroyed but we got everyone out and thankfully nobody was hurt. It could easily have been much worse because the building contained a lot of flammable liquids for the printing as well as gas cylinders."

According to a notice on Arden Direct's website, dated 4 January, the company's servers have been reinstated and it is now going through the backlog of data and emails from 29 December, while telephone calls are being redirected to a new temporary office.

Arden's mailing production and despatch department for bulk mailings will "remain inoperable for the medium term". However, the company said it had negotiated arrangements with industry partners to allow it to complete work.