George Davies, the fashion designer whose Per Una clothing range has helped to revive the fortunes of Marks & Spencer, is under investigation by the Inland Revenue.

Officers from the Inland Revenue's special compliance unit, which investigates suspected serious fraud or allegations of substantial cases of avoidance or evasion, took documents and computer files from Davies' Cotswold home and the Per Una head office in early morning raids last week.

Mr Davies is co-operating with the investigation and says he is unaware of any allegations made against him. M&S, meanwhile, said: "This is a personal matter for George. It has nothing to do with M&S."

The Per Una range was launched at M&S last year and is the first non-M&S branded range on sale. Before launching Per Una, Davies shot to fame with the success of Next and the George at Asda label.