A van containing the homemade mortar bombs was stolen in Newry last Saturday and was discovered last night by a Special Branch Patrol from Dundalk during a routine check of vacant houses about two miles south of the border.
The van was loaded with six large homemade mortars with holes cut in the roof of the van to enable them to be fired.
It is believed the mortars were to be used by the Provisional IRA in an attack on a British Army or RUC installation.
Army explosive experts were called in.
The reporter is Tom McCaughren.