SECURITY chiefs fear Al-Qaeda terrorists trained as scuba divers could mount attacks against a royal review of the fleet being held to mark the 200th anniversary of the battle of Trafalgar.

A senior Ministry of Defence (MoD) police officer has disclosed that militants using techniques learnt in western diving schools to attack Royal Navy ships are considered the main threat to the event.

Officials fear Al-Qaeda divers could attach bombs to the hulls of the ships, detonate explosives strapped to their bodies in suicide attacks or even board vessels and kill some of those on board.

The Queen, in her office as Lord High Admiral, will review about 40 ships from the navies of nations including France and Spain. She will be on the deck of one of the Royal Navy ships.

The review of the fleet, which takes place on June 28, is the first in a series of events celebrating the 200th anniversary on October 21 of the battle in which Nelson destroyed the Franco-Spanish fleet.

Sovereigns have reviewed their fleets in the Solent off Spithead, Portsmouth, since the 15th century. The most recent occasion was in 1977.

In previous reviews, small boats and yachts have mingled with the naval vessels but this event, the first since the September 11 attacks, will be different.

The 3,000-5,000 private yachts and small boats expected to gather in the Solent to watch the review will be kept away from the naval vessels in the main channel.

There will be a 200m exclusion zone around the naval ships and strict rules preventing “fast planing boats” from sailing at anything above minimum speed. Although that rule was ostensibly imposed to reduce the danger from wash, security sources have said it is designed to prevent terrorists using fast boats to mount bomb attacks similar to those carried out by Al-Qaeda on a US ship off the coast of Yemen in October 2000.

Small boats taking part in the Spithead review will be kept back against the shore away from the main route by marshals. Privately, however, officials admit it will be almost impossible to control the number of small boats attending and there will be no attempt to impose a pass system.

The MoD police’s marine units and Hampshire police, who are responsible for security at the review, will concentrate on maintaining the exclusion zone round the fleet, although all boats will have access to other parts of the Solent.

They believe the only way terrorists will be able to get through the security cordon would be underwater, which is why the threat from terrorist divers linked to Al-Qaeda is taken seriously.

One senior MoD police officer said: “It is something that really concerns us and has done for some time. The potential is obviously there. It presents a very difficult problem for the officers on patrol.”

Bruce Jones, chairman of a Nato security policy group, said the use of sub-aqua techniques fitted the Al-Qaeda modus operandi.

“Scuba-diving is fairly user-friendly,” he said. “It’s not high-technology and it’s not expensive. It is the type of thing a deep-cover Al-Qaeda cell could manage fairly easily.”

A number of Royal Navy vessels now have machineguns mounted on their decks to defend ships against possible “swarm attacks” by terrorists in boats. That measure was taken in 2002 in the wake of the arrest, during a joint UK- Moroccan operation, of an Al-Qaeda cell based in Morocco that was planning to attack Royal Navy vessels in the Straight of Gibraltar.

Although any underwater diver could be picked up on the navy ships’ sonar systems, they are not sophisticated enough to distinguish between a man and an ocean-going mammal such as a seal or a dolphin.

Even if they were picked up, the use of a swarming technique would hamper the authorities’ efforts to prevent an attack. “The point of a swarm attack is that you might stop some of them but some of them will get through,” said Jones.

The suggestion that Al-Qaeda might attempt swarm attacks using men trained in diving skills is not new. For the past three years, the FBI has been investigating reports of Middle Eastern suspects approaching scuba diving clubs in America and inquiring about training.

The bureau’s investigation was widened after the Dutch security service, the AIVD, discovered suspected Islamist extremists had been trained at a diving school in the Netherlands.

Several of the 48 Arabs trained to dive at the Eindhoven club were among a dozen alleged militants later charged with trying to recruit Dutch Muslims to join Al-Qaeda. Although all those charged were freed when the case collapsed, the AIVD insists the file remains open.

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