A statement from the Police Service of Northern Ireland said:
Detectives from the PSNI's Serious Crime Branch, with assistance from officers in Cumbria Constabulary and the North West Counter Terrorism Unit, are conducting a number of searches in Northern Ireland and north west England.
The search activity is in connection with the wider investigation into the murder of PSNI Constable Ronan Kerr in April 2011 and linked incidents.
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Kerrie Gosney brings you Sunday night's forecast
The party leader said her MPs may be in a position to act as deal makers - and they would refuse to allow an exit from the EU.
Rain spreading east Sunday. Decent day on Monday, more changeable thereafter