Food companies were accused yesterday of "irresponsibility" in hampering an investigation into the outbreak of BSE.

Government scientists, who have been asking for company records since 1996, have complained to the chief medical officer about their "reluctance" to help with research into the disease by hiding behind a cloak of commercial secrecy.

Celia Bennett, director of the British Meat Manufacturers' Association, denied the claims. "We are doing our utmost, and are in discussion with the Food Standards Agency and advising our members about it and acting as an intermediary on this issue," she said.