The Northern Ireland Secretary, Dr Mo Mowlam, has condemned the Wednesday night firebomb attacks on shops in Portadown as a "cynical and sinister assault".
A furniture store was destroyed and two other premises were damaged by fires estimated to have cost hundreds of thousands of pounds in damage. Earlier in the day an incendiary device was defused in a clothing store in the town.
Dr Mowlam said: "There is little doubt that the perpetrators of these sinister crimes are cynically trying to stoke up sectarian tension in the area. But right-minded people will resist them and we will not allow criminals to divert us from the rule of law and the path towards peace."
The fires, blamed on republican paramilitaries, came after the Portadown Orange Lodge had pledged to step up its series of protests against the Parades Commission decision to reroute its Drumcree march.
A Sinn Fein Assembly member for Upper Bann, Ms Dara O'Hagan, has called on those responsible for the attacks to cease their activities immediately. "Apart from the fact that there is no justification for this campaign, those responsible should recognise the damage being caused to the efforts to create a political climate in which we can bring all sections of society together."
The attacks were also condemned by the Co Armagh Orange Grand Master and Independent Unionist Assembly member, Mr Denis Watson.