Toxic attack on city is 'likely soon'
By Jimmy Burns and Mark Huband in London
Published: January 10 2003 22:00 | Last Updated: January 10 2003 22:00

British ministers have been warned by their security advisers that a west European city is "likely" to be the target of a terrorist attack using a chemical or other non-conventional weapon in the short-to-medium term.

They have also warned that they cannot be sure they know the identity of more than 50 per cent of people in the UK who might carry out a terrorist attack on behalf of al-Qaeda.

In a separate incident on Friday morning German authorities arrested two Yemeni men believed to be high-ranking members of al-Qaeda, according to German security officials. The federal crime office confirmed that two men were arrested at a Frankfurt airport hotel, on the request of US authorities. One of the men is a senior al-Qaeda financier and both had been involved in building al-Qaeda's network in Yemen, security officials were cited as saying.

Fears that al-Qaeda terrorists are closer to carrying out a chemical attack have been heightened by the discovery this week of traces of ricin at a house in London occupied by suspected terrorists.

Seven men arrested in connection with a suspected plot to use the deadly poison were still being questioned by anti-terrorist police in the UK on Friday and were expected to by charged this weekend.

Security sources in Britain say that it is "certainly a possibility" that the ricin poison made in London might have been taken abroad.

It is not clear from the traces found at the north London flat how much ricin might have been produced and possibly hidden elsewhere. Nor is it clear how many more individuals might have been working with those now under arrest.

Sources said that efforts by the UK anti-terrorist police to identify terrorist operatives handling ricin are now being replicated in European countries that have been specified by al-Qaeda as targets.

"While everyone is looking at what the British can turn up, there is a fear that similar threats could be activated by 'sleepers' in mainland Europe. You won't be told about it publicly but we are all racing to try to see what we can find," a European security source said on Friday.

The information that led to the London arrests did not come from abroad, though a key part of the suspects' interrogation will centre on any ties they may have to other countries, in particular the north African populations in France and Spain.

US concerns about the use of ricin led the FBI on Friday to issue a special bulletin alerting US police to the dangers of the deadly toxin. In a special edition of the FBI Intelligence Bulletin the agency gave a detailed explanation off its potential uses and effects.

Additional reporting by Hugh Williamson in Berlin