The RUC has detained three men and three women in connection with the discovery of a 350lb primed bomb near Omagh in Co Tyrone last night.
The device was discovered inside a milk churn in a shed at the rear of a house in Sixmilecross.
The RUC believes the bomb was assembled by dissident republicans.
A husband and wife were detained last night following the find, while another two men and two women were arrested today during follow-up searches in Newtownbutler, Co Fermanagh.