Suspected explosive devices sent to armed forces recruitment offices bear “hallmarks of Northern Ireland-related terrorism”, a Number 10 spokeswoman has said.
One of the suspicious packages was stamped with a Republic of Ireland postmark but no specific group has claimed responsibility for the attack.
Prime Minister David Cameron chaired a meeting of the Government’s Cobra emergencies committee to discuss the suspicious parcels, which sources said were “crude” in design but “could have caused injury to others”.
A Number 10 spokeswoman said: “Seven suspect packages have been identified as containing small, crude, but potentially viable devices bearing the hallmarks of Northern Ireland-related terrorism.
“These have been safely dealt with by the police and bomb disposal units. Guidance has been issued to staff at all military establishments and Royal Mail asking them to be vigilant and look out for suspect packages, and the screening procedures for mail to armed forces careers offices are being reviewed.”
Four parcels were discovered at Army careers offices in Oxford, Brighton, Canterbury and Slough yesterday.
One package was found in Aldershot on Wednesday, while two packets were found on Tuesday at military careers offices in Reading and Chatham, Kent. Detective Superintendent Stan Gilmour said: “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.
“When a suspect package is reported we have a routine response which means we may need to evacuate the area if necessary.”
It is understood a suspected package found at RAF Mildenhall in Suffolk was a false alarm and is not related to the investigation at the recruitment offices.