Security forces in Dungannon Co Tyrone are searching an area of the town after a telephoned warning by a man claiming to be from the loyalist group the Red Hand Defenders.
The call to a Belfast newspaper claimed a device had been left outside the courthouse in Dungannon on Killyman road. The security operation is continuing, an RUC spokeswoman said.
In Belfast part of the Ormeau Road at South Parade has been sealed off after an object was found close to the Northern Bank.
In Co Derry two pipe bombs were found in a sports ground in. British army bomb disposal experts were called to deal with the devices which were uncovered during a search of Desertmartin GAA ground near Magherafelt.
They were found near an entrance and by a perimeter fence. Two other bombs have also been defused in Garvagh and Gulladuff.
Yesterday security forces dealt with a series of bomb alerts across the North including one claimed by the Red Hand Defenders - a cover name used in the past for both the UDA and the LVF.
As it claimed planting the booby-trap device under the van of what it called "a well-known republican" in Armagh the group said: "Our campaign will increase."
Last month the group admitted killing Protestant teenager Gavin Brett in Glengormley, Co Antrim last month .
SDLP chairman Mr Alex Attwood and Sinn Fein MLA Mr Conor Murphy today called on the Northern Ireland Secretary to constantly review the UDA ceasefire.