Armagh will be without defender James Morgan for their Division Two encounter with Ulster rivals Fermanagh on Saturday.
Component parts for mortars were found in a forested area between Forkhill and Jonesborough.
Police say Bushmills blaze was arson while firefighters are at the scene in Armagh.
Donegal boost their Division Two promotion hopes with a 1-9 to 0-11 victory over Armagh in a tight tussle at a windswept Ballybofey.
Armagh assistant manager Jim McCorry says his side will expect a backlash from Donegal in Saturday’s Division Two clash in Ballybofey.