AT LEAST eight people were injured when an explosion ripped apart a double decker bus in central London last night.
The latest blast, in Wellington Street near the Aldwych, came just lb days after the Docklands bombing and the end of the IRA ceasefire.
Scotland Yard said it got no warning of the explosion, which happened at 10.38 p.m. near the heart of the capital's entertainment area at Covent Garden.
Early this morning, police were making no comment about any fatalities, amid unconfirmed reports that three people may have died.
The British Prime Minister, Mr John Major, was being briefed by officials at 10 Downing Street early this morning.
While no admission of responsibility had been received by police, politicians in London and Belfast immediately feared a lethal escalation of the renewed IRA campaign.
The swift response of the Irish Government to last night's events seemed to further dispel any initial hopes that the IRA might not be responsible. The Government condemned the blast as "an appalling outrage".
The President, Mrs Robinson, in a statement issued in New York last night, expressed her "deepest dismay" and offered her sympathy to all those affected by the explosion.
The imperative for both governments now will be to determine a political way forward.
But if a summit between Mr Major and Mr Bruton is now more likely, and more urgent, the options available to them have been further dramatically reduced.
Even before last night's events, the Ulster Unionists and the DUP were pressing Mr Major to push ahead with his plans for an elected body in the North. Mr Major is due to see the SDLP leader, Mr John Hume, to discuss the issue at Downing Street later today.
But even if he could overcome the SDLP leader's objections to the scheme, the original purpose to bring unionists and Sinn Fein to the same conference table would appear to be lost.
With clear signs of a hardening of opinion on the Conservative backbenches, and given his increasing reliance on Ulster Unionist support in the Commons, Mr Major is likely to intensify pressure on the SDLP and Dublin to devise a process with which the North's constitutional parties can engage.
The deputy leader of the DUP, Mr Peter Robinson, last night called on the international community to crush the Provisional IRA and said this would require the restoration of internment.
Six people - five men and a woman - were rushed to St Thomas's and University College hospitals. One was said by hospital personnel to have serious head injuries and was taken straight to theatre for surgery.
It is believed the explosion took place on the upper deck of a 171 bus on the New Cross to King's Cross service, which had. just travelled across Waterloo Bridge.
Eye witnesses said the bus was "split half way - torn apart really" and expressed disbelief that anyone travelling on it could have survived.
People on the streets, leaving nearby pubs and restaurants, described harrowing scenes of suffering and panic.
A Canadian law student Mark Johnson (25), had been drinking with friends in the nearby Wellington pub when the explosion sent shards of steel and glass over an area of at least 50 yards.
"I saw a woman lying in the street in a pool of her own blood," he said: "There was a great deal of debris and shattered steel.
"We were all in a state of complete panic. The bomb was on the bus. It blew the whole of the top deck clean off. It was definitely planted on the bus. There was no ceiling, no roof."
A spokeswoman at St Thomas's said three of the six people admitted had significant head injuries. The other casualties had minor superficial injuries and lacerations to the body. Two were in severe shock.
The man immediately taken to theatre had "significant facial injuries and arterial bleeding". The hospital was not expecting any further admissions early this morning.
Political reaction was swift. Mr Andrew Hunter, vice chairman of the Conservative backbench committee on Northern Ireland, said: "On the assumption that this is another IRA bomb, our worst fears are fulfilled.
"It is another horrific outrage. It is sickening and there is no justification."
Mr Hunter said "obviously the ceasefire we now consign to history."
Declaring that there could bed place for Sinn Fein in any negotiations, Mr Hunter said this, sadly, "means we must prepare ourselves for further violence.
And Mr David Wilshire MP said he would be seeking to table amendments to extend the Northern Ireland Emergency Provisions Bill by a further two years, when the measure comes before the Commons this evening for its third reading stage.
Mr Wilshire said: "It is not a warning shot across the bows. It would appear to have been planned for some time.
"It has noting to do with planned elections in Ulster and everything to do with the conclusion that the IRA has come to that it is not going to get a united Ireland through talks, and will only do so through bombing the English into submission."