A 46-year-old man was arrested in Coalisland this morning as part of an operation against dissident republican terrorist activity.
Police carried out a number of searches and made a total of four arrests in both Coalisland and Lurgan.
Houses were evacuated in the Woodville Avenue area.
Two of those arrested are 22 years old, one is 24 and the fourth is 46.
Three were arrested in Lurgan and one in Coalisland.
They are being questioned at a Belfast police station.
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