Bernard Matthews, Britain's best-known turkey breeder, could face prosecution over lapses in hygiene at his plant at Holton, Suffolk, where thousands of birds were slaughtered last month after an outbreak of avian flu.

A government report says inspectors who visited the site in January saw gulls feeding from uncovered waste bins, carrying turkey waste away and roosting on the roof of the turkey houses.

An inspection of the infected plant showed several points where rats, mice and small birds could get in. Polythene bags of waste had been left where they could have been blown about. There were also "extensive" leaks in the ceiling, which could have allowed infection by rain.

But despite finding droppings that showed wild birds had been in the infected shed, the Department of Environment (Defra) inspectors seem to have ruled out their original theory that the infection came from a wild bird. A second Defra report concluded Hungary was the "most plausible" source of the infection.