A man has been arrested in Co Londonderry bringing the total number of arrests following disruption last week to six.
A 48-year-old man was arrested following a search of a property in the Victoria Place area of Derry on Sunday, as part of what the PSNI have described as an "ongoing terrorism investigation".
To date in that investigation, two men aged 22 and 41 and a 26-year-old woman were arrested on Thursday, one woman aged 50 was arrested on Friday and a 43-year-old man was arrested on Saturday, all arrested under the Terrorism Act.
The 50-year-old woman was released from custody on Sunday evening.
Patrick Madden, solicitor at Madden & Finucane - representing the woman, said she was questioned for three days in the Serious Crime Suite at Musgrave Street Police Station in Belfast.
Mr Madden said: "She has maintained her innocence throughout police questioning over three days.
"She has now been released without charge and will be reunited with her family."
On Friday, 16 officers were injured in the Creggan area, with a PSNI spokesperson saying that a large group of people gathered from 6pm and threw missiles at officers, including petrol bombs and masonry.
Searches in Derry over the last several days have produced a number of explosive devices, as well as guns and quantities of ammunition.
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