A warning issued by the British Home Office over the danger of a nuclear or chemical terror attack by the al-Qaeda network was retracted within an hour and substituted with a milder warning.
It is thought the U-turn may have been prompted by fears that the original version could cause panic.
Dramatic details of a potential threat came in a security assessment issued under the name of Home Secretary Mr David Blunkett. Al-Qaeda, suspected of being behind the September 11 attacks on the United States, might be ready to use "a so-called dirty bomb, or some kind of poison gas", the assessment said.
The Islamic militants thought to be behind the September 11th attacks could turn to trains and boats to strike at the heart of Britain's cities, it warned.
But that assessment was rapidly retracted by officials who wanted it shredded and was replaced with a blander warning about attacks on "key economic targets or upon our transport infrastructure".
The original warning came in the foreword to a summary of anti-terrorist measures taken by Britain in recent months. It was published as Mr Blunkett and British intelligence chiefs met US homeland security chief Mr Tom Ridge.
It had warned: "They [terrorists] may attempt to use more familiar terrorist methods, such as leaving parcel or vehicle bombs in public places, to hijacking passenger aircraft. However, they may try something different, perhaps as surprising as the attacks on the World Trade Centre, to the theatre siege in Moscow.
"Maybe they will try to develop a so-called dirty bomb, or some kind of poison gas; maybe they will try to use boats or trains rather then planes. The bottom line is that we simply cannot be sure".
A Home Office spokeswoman said the first version was "an early draft" that had not been authorised by the home secretary. "We did not want to close people's minds to other forms of risk or threat - we didn't want to have something where the public thought 'that is what we are looking for'," she said. "We wanted a general reminder for a general threat".
AFP