Home Office warnings that a dirty bomb attack on a major transport area in Britain are now ‘more realistic’ following the claim that at least 20 pro-al-Qaeda-trained men are at large in the country have not been made to marina bosses.

Tony Keeler, managing director, of Britain’s largest marina operator, MDL, said:’If the government are now running this higher up the flagpole, then we have had no consultation from anyone.’

The Home Office said serious work was underway in Whitehall to protect Britain against the use of a chemical, biological or nuclear dirty bomb against shopping centres, railway stations and ports. Thousands of civilian workers in shops, restaurants and bars are being trained in these terminals.

But so far marinas are excluded, said Keeler. ‘We’ve set up our own code of practice and observation is our first weapon. But we’ve been given no consultation about a dirty bomb. There is a growing expectation that something of that ilk is going to happen somewhere in this country and let’s face it we have a very big gate to secure: namely the sea or a river. We will take every precaution and common sense is on red alert.’