The airports authority BAA wants to introduce a high tech scientific dossier containing profiles of "normal" airline passengers, with options to impose an extra layer of security checks and searches on travellers who do not conform.

The plan comes after revelations that a television producer smuggled an imitation semi-automatic handgun onto a British Midland flight at Heathrow.

A department of transport spokesman said that Alistair Darling was "extremely concerned" over the security breach.