A number of people have been arrested as part of a major police operation targeting dissident republican activity in the North.
Specialist search teams from the PSNI are examining several properties in the Lurgan area of Co Armagh.
DUP MLA Carla Lockhart said up to 15 homes had been evacuated.
She said: "The PSNI are sending out a very clear message - terrorist activity, no matter what level, will simply not be tolerated.
"Nobody wants to see terrorist activity here and this operation in north Lurgan has once again thwarted the aims of those groups who want to drag Northern Ireland back into the past.
"Dissident activity has no place in this community."