Tension in Northern Ireland was at its highest level in recent years after further shootings last night and a statement from the IRA warning of "a crisis in the peace process".
A Catholic father of three, Mr Benedict Hughes (55), of Suffolk Crescent, in west Belfast, was shot as he got into his car after finishing work at a motor components store near the loyalist Sandy Row area of the city.
A lone gunman fired at least five bullets into his neck and chest. Mr Hughes died a short time later in the Royal Victoria Hospital. A number of arrests were made.
Another man was undergoing emergency surgery at the hospital after receiving multiple injuries to the stomach and neck in a separate incident. Two men wearing balaclavas burst into the home of Mr Steven Paul, a married man in his early 40s, at Minnowburn Drive, on the predominantly Protestant Belvoir Park Estate on the outskirts of south Belfast, shortly before 11 p.m. They shot him several times and his condition early this morning was described as critical.
In a further incident Mr John McFarland, a taxi-driver working for a Catholic-owned firm, was shot and injured in the north of the city around 9 p.m. However, he was able to drive himself to the Mater Hospital. He is not believed to be seriously hurt.
There was no immediate claim of responsibility for any of the attacks, but the killing of Mr Hughes was being widely blamed on loyalists, either the Loyalist Volunteer Force, who have claimed a number of recent killings, or the UDA-UFF.
The North's Political Affairs Minister, Mr Paul Murphy, said: "This gruesome round of killings must stop now. They achieve nothing other than to satisfy the blood-lust of evil people."
The Presbyterian Moderator, Dr Sam Hutchinson, has called for the talks process to continue as a matter of urgency following the latest sectarian killings.
"If these murders are designed to wreck the political talks that strategy must not be allowed to succeed . . . An accommodation must be found that will command the support of reasonable people across the community, of which I believe there are many," he said.
The SDLP leader, Mr John Hume, said those responsible for recent murders were "attempting to provoke a resumption of the IRA campaign".
The Ulster Unionist deputy Lord Mayor, Mr Jim Rodgers, said the killers of Mr Hughes were "evil, cowardly and hell-bent on bringing about a reaction from republican paramilitaries".
The Sinn Fein president, Mr Gerry Adams, said the Orange card was being played and unionists and loyalists were trying to "bully the two governments and terrorise the nationalist people".
In a further sign of a deteriorating situation, the IRA said in a statement issued to the BBC that the recent set of Propositions on Heads of Agreement issued by the British and Irish governments was "a pro-unionist document and has created a crisis in the peace process".
Pointing out that the organisation had maintained a ceasefire since last July, the IRA statement accused the British government of avoiding its responsibilities in the peace process.
Sources close to republican thinking said last night that despite a "huge strain" on the ceasefire the IRA had kept "its side of the bargain" but there had been "no delivery" from the British government.
The propositions paper had been a "gamble" based on the assumption that giving into the unionists would persuade them to engage fully in the talks.
The document had caused "enormous difficulties" inside the republican movement and the leadership would be watching with great interest to see how the two governments would respond if the unionists continued to "filibuster" the talks.
Although the administration in Dublin is not mentioned by the IRA, there is a strong feeling in republican circles that they have been let down in this quarter also. Even British sources are suggesting that "Dublin got it wrong".
Republican concerns were expressed in very clear terms by Mr Adams at a private meeting with the Taoiseach in Dublin last Friday. Senior sources described the encounter as "tough" and said Mr Ahern was shaken by what he heard.
The SDLP leader said the UUP had been giving the impression that it was directly negotiating with the Prime Minister but Mr John Hume was "quite convinced" no concessions of any description had been made by Mr Blair. The ICTU will hold a public demonstration with a demand to "Stop all the Killings", on Friday week in Belfast.