About 70 rounds of ammunition and components, which could be used in a bomb, have been found dumped in a field in north Donegal.
The bullets, mostly .22 calibre used in handguns and hunting rifles, were found on farmland in the Killea area near Bridgend and the border with Northern Ireland.
Electrical components which could have formed part of an explosive device were also recovered but no explosive material, a garda spokesman said.
A handful of other ammunition was also recovered in the planned search.
It is understood the garda-led operation was launched on Monday evening after a tip-off and lasted until lunchtime.
Roads in the area were closed for several hours but no homes were evacuated.
Bomb disposal officers from the Defence Forces explosive ordnance division were called to assist.
An Army spokesman said: "A number of items were removed and they are going to be examined."
He added: "The items found include a quantity of small arms ammunition and components which could potentially be used in the construction of an Improvised Explosive Device (IED).
"Some of the items were handed over to the gardai for their investigations, and a number of components were removed by the bomb disposal team for further analysis."
© Press Association