Ireland's police force says its detectives have arrested nine suspected Irish Republican Army dissidents and seized weapons.
Friday's arrests follow a British government decision to raise its warning of possible attacks by IRA splinter groups in England. Irish authorities say they agree with that threat assessment.
The dissidents oppose the IRA cease-fire and wider Northern Ireland peacemaking. They last mounted an attack in England in 2001 but remain active in Northern Ireland, detonating six car bombs this year.
Police say they arrested two men aged 20 and 33 at a house near the Northern Ireland border and seized a gun and ammunition.
They arrested seven people aged 19 to 71 in southeast Ireland and sealed off a home where they found bomb components.