Security stepped up after attack

Police have increased security at potential terror targets after the blast at MI6 headquarters by suspected dissident Republicans.

Police have increased security at potential terror targets after the blast at MI6 headquarters by suspected dissident Republicans.

They have warned that the Real IRA - thought to be behind the attack - are planning further outrages.

Anti-terrorist officers fear next week's Labour Party conference could be on the bonmbers' hit list and have put it on a state of high alert.

Security chiefs believe the Real IRA - which is opposed to the Northern Ireland peace process and which bombed Omagh, killing 29 people in August 1998 - was behind the attack on the top-security building on the south bank of the Thames in central London.

A senior security source cautioned: "This is clearly an organisation which is becoming more and more aggressive and confident of what it can achieve and sustain.

"It has the capacity to strike right at the heart of London. It has an overseas team in place, indicating it's a force to be reckoned with."

Sussex Police immediately announced it is stepping up security at Labour's Brighton conference.

It has spent months planning for the first Labour conference for three years in the seaside resort.

Brighton already has a bloody history, with five people being killed in 1984 when the IRA bombed the Grand Hotel during the Conservative conference.

Codenamed Operation Otter, officers are to create a "secure island" around the Brighton Centre, the venue for the four-day conference, and neighbouring hotels The Grand and The Metropole, which will accommodate delegates.

A temporary bridge linking the Metropole with a car park behind the Brighton Centre will allow delegates to come and go without passing through security checkpoints.

But today Sussex Assistant Chief Constable Nigel Yeo announced security arrangements were being reviewed and warned there may be greater disruption to local residents as a result.

He said: "Our security operation for the conference has been many months in the planning but it has a built-in flexibility to enable us to adjust our level of response according to the security threat.

"Clearly we cannot ignore the implications of last night's incident in London.

"Among other measures, people are likely to see an increased number of police road checks not just in Brighton but across Sussex. I am sure people will understand the need.

"I would also ask people to act as our eyes and ears to ensure the safety of everyone."

If last night's attack, which looks likely to have involved the use of a rocket-propelled grenade, does prove to be the work of the Real IRA, it would be its third attack on the British mainland this year.

The group is thought to have been responsible for this summer's bomb attacks on Hammersmith Bridge and a railway line at Ealing Broadway.

Although it called a ceasefire in the aftermath of the Omagh tragedy, it is now known to be active again and security services in Northern Ireland are on full alert.

Earlier this month, it was suspected of a mortar attack on the Royal Ulster Constabulary station at Armagh.

It also fell under suspicion the previous day when two 80lb bombs were found at a military training camp at Magilligan, County Londonderry.

The prospect of an active terrorist group at large on the mainland, apparently equipped with at least one rocket launcher, prompted an immediate upgrading of security at other security-sensitive buildings.

In London, Metropolitan Police Deputy Assistant Commissioner Alan Fry, head of Scotland Yard's anti-terrorist branch, who is leading the investigation, said the device used against MI6 was possibly a rocket launcher.

He said: "Clearly the sort of weapon we believe was used in this attack is known to be in the hands of certain groups. They will be uppermost in our minds.

"Certainly there have been finds in both the south and north of Ireland and similar devices may have been used here.

"Clearly we have to keep in mind the capabilities of dissident Irish groups, but at this stage we will not be ruling out any group who might see the Secret Intelligence Service as a target."

Mr Fry, who said the device was fired at the building from a range of between 200 to 500 metres, added that there had been no warning, nor had there been any claims of responsibility.

Neither MI6 nor the domestic security service, MI5, are believed to be involved in the investigation.

The attack, which was launched without warning at 9.45pm, damaged a window, two panels and a section of the metal frame of the eighth floor of the distinctive green and cream MI6 building.

Police officers spent much of the day scouring an area stretching 500 yards around the building. The search also took in nearby railway lines running into Waterloo station, prompting speculation the missile could have been fired from the tracks or nearby.

The investigation caused significant disruption to London commuters. Major roads around the building in Vauxhall Rail were closed for much of the day and rail services, including Eurostar, were badly disrupted.

Foreign Secretary Robin Cook, who has responsibility for MI6, praised the service's staff for continuing to work today.

"If the intention of the attackers was to disrupt SIS's operations, they have failed in their objective," said Mr Cook.

Anyone with information about the attack is urged to contact the Anti-Terrorist Branch on 0800 789 321.