Attacks a bitter blow for UK security teams

LONDON - For Britain's security services the bombings were a bitter blow.

Having stopped no fewer than five major al Qaeda plots in Britain, they had finally "let in a goal". And all the time the police and security apparatus has to bear in mind the possibility that the bombers escaped and have the resources to strike again.

Police are seeking reports of anyone seen acting suspiciously around lock-ups or garages over the past few days and are talking to landlords who have taken on new lodgers recently, or received inquiries from people wanting short-term lets. The British Transport Police have even brought in their pickpocketing squad to trace the possible route of the bombers' journey to King's Cross.

The bombs themselves were just under half the weight of and fewer than the devices which killed 191 people on Madrid trains in March last year.

One expert said: "It was small, simple and didn't require a lot of people, which would have helped to keep it below the radar of the security services. I don't think we are dealing with the same people who carried out the Madrid or Istanbul bombings."

Britain keeps tight control of explosives. In Spain the explosive was found to have been stolen from a quarry. One theory being pursued is that the material for the bombs was brought in from outside, and other security services are being asked to explore the possibility that there was an Irish or French connection.

Early speculation in the wake of the blasts was of a North African connection. Mohammed al-Garbuzi, a Moroccan linked to Madrid as well as suicide bombings in Casablanca in 2003, is a name being mentioned. He disappeared from his north London home shortly after the Madrid attack. He denied any involvement in an interview with Al Jazeera.

The man believed to be the Madrid mastermind, Mustafa Setmarian Naser, a 47-year-old Syrian with dual Spanish nationality, is said to be "one of many suspects" being hunted by the police and MI5.

They also want to question Zeeshan Hyder Siddiqui, 25, a British national allegedly trained to make bombs in an al Qaeda camp who was arrested in Pakistan in May.

"We are convinced it is not a British-based cell," a senior Government source said. There was a strong possibility that the bombers came from Iraq and spent time in mainland Europe before entering Britain recently.

The worst fear of the security services is that the bombers might be "clean skins" - newly recruited or British-born extremists with no police or intelligence records, perhaps trained, equipped and directed by a much more experienced terrorist. If they were not Muslims, they would be even harder to detect.

"A spate of individual fanatics, each committing an act of horrendous terrorism, is what senior MI5 officers lie in bed sweating about at night," said one former intelligence officer.

The major line of investigation is that the bombings were carried out by an alliance of terrorists formed for this operation. The cell responsible could involve unaligned, free-floating terrorists not directly involved with the better-known groups. Their temporary existence has made it hard for the agencies to build up data about their membership and whereabouts.

- INDEPENDENT