Search procedures at a Northern Ireland prison are under urgent review after the discovery of a bomb detonator.
The device was found at Maghaberry Prison during a series of searches ordered after a bullet exploded in a toaster.
Police believe the discovery of the detonator may be linked to a campaign by loyalists and republicans demanding to be segregated.
The detonator was found in Bush House at the top security jail near Lisburn, Co Antrim.
The discovery followed the detection of two other bullets in the Roe House and Bush House wings after the alert was sparked by the explosion of the bullet last Thursday.
Visits were halted because of the find and more searches are to take place.
"It's a very serious incident which jeopardises the safety of staff and prisoners," a prison service spokesman said.
"These are small devices which can be difficult to detect by normal metal detection methods. We are urgently reviewing our search procedures to see how such incidents can be prevented in the future without implementing draconian security measures."