The leaders of the North's two largest unionist parties descended into a public slanging match on the streets of east Belfast yesterday.
UUP leader David Trimble, flanked by members of his party, engaged in a schoolyard spat with senior DUP figures after the anti-agreement party provocatively arrived outside the Ulster Unionist headquarters.
In traditional fire-and-brimstone rhetoric, DUP leader Ian Paisley taunted his opposite number.
``The wicked fleeth when no man pursueth,'' he declared, predicting the UUP's defeat at the hands of the people of Ulster.
``They will remember the Ulster Unionist Party's record of failure over the past five years,'' he prophesied.
Against the backdrop of the latest mocking DUP billboard advertisement, he continued his tirade against Trimble's deceit, feebleness and ``double-dealing''.
``The day of reckoning has now come,'' he said.
But Mr Trimble, apparently sensing an opportunity to provoke the unstable Mr Paisley into a rash remark, emerged surrounded by a coterie of followers.
``When are we going to have a debate Ian? When are you going to stop running?'' he shouted, between forced laughs.
The encounter quickly degenerated into a public display of unionist dysfunction, with schoolyard jeering and hissing threatening to erupt into a slap-fight.
Bellowed accusations were met with mocking retorts. ``Where's Jeffrey Donaldson?'' demanded the DUP amid a chorus of ``Traitor!''
Incoherent and meaningless insults continued, back and forth, until Trimble slipped down an alleyway and was gone.
Mr Donaldson himself said the incident could be hugely damaging to unionism.
``Unionists who continue to indulge in the luxury of that kind of confrontation will ensure we will continue to lose out to the nationalist and republican agenda.''
South Antrim rebel Ulster Unionist David Burnside demanded both parties sit down together once the election was over.
``This bickering and public in-fighting is a massive, massive turn-off to the unionist population,'' he said. ``I am not attributing blame but it was absolutely disgraceful and must stop.''
The Alliance Party said the spat had been ``childish and pathetic''.
Hardline unionists were blamed today for a paint bomb attack on David Trimble's constituency office.
Less than 24 hours after the street bust-up, red and white paint was smeared on the front door of the Upper Bann office in Lurgan, Co Armagh.
Mr Trimble was not in the premises at the time.
A spokesman for the Ulster Unionist Party leader did not accuse the DUP of any involvement.
But he added: ``It seems a bit strange that a day after Mr Trimble takes on the DUP outside his party HQ, something like this happens.''