Hmmmm. Does anyone remember that movie Blast From the Past?
It is feared that terrorists could transport an improvised nuclear device up the Thames and detonate it in the heart of London. Bristol, Liverpool Newcastle, Glasgow and Belfast are also thought to be vulnerable.
Lord West, the Security Minister, also raised the possibility of terrorists using small craft to enter ports and launch an attack similar to that in Mumbai in 2008, when more than 150 people were killed.
The Government is so concerned about the threat that it is setting up a command centre to track suspicious boats.
The International Atomic Energy Authority recorded 1,562 incidents where nuclear material was lost or stolen between 1993 and 2008, mostly in the former Soviet Union, and 65 per cent of the losses were never recovered.