LONDON -- The British government said Thursday that crude but viable package bombs sent to seven British army recruitment offices appear to be the work of Northern Ireland militants.
Prime Minister David Cameron's office said the suspicious packages contained "small, crude, but potentially viable devices bearing the hallmarks of Northern Ireland-related terrorism."
Cameron was briefed on the finds at a meeting of the government's crisis committee, known as COBRA.
His office said the devices "have now been safely dealt with by the police and bomb-disposal units."
Police said suspicious packages were found Thursday at army career offices in the towns of Oxford, Slough, Canterbury and Brighton, while similar packages were discovered earlier this week in Aldershot, Reading and Chatham.
Police said the packages' contents were being sent for forensic examination.
"Even if the contents are determined to be a viable device they pose a very low-level threat and are unlikely to cause significant harm or damage," said Detective Superintendent Stan Gilmour of the Southeast Counterterrorism Unit.
Police said all military facilities and post offices had been told to be "extra vigilant."
Irish Republican Army dissidents opposed to the peace process have mounted gun and bomb attacks in Northern Ireland in recent years, killing two soldiers, two policemen and one prison officer since 2009. In October they were blamed for sending letter bombs to high-profile political and security figures in Northern Ireland.
But they have not attacked mainland Britain since 2001, when car bombs outside the BBC headquarters, a London nightspot and other buildings wounded several people.
Britain's threat level from international terrorism stands at "substantial," the middle rung on a five-point scale. The threat from Northern Ireland terrorism is one rung lower, at "moderate."
The prime minister's office said the threat level "remains under constant review."