A group using the name of the IRA has claimed responsibility for a series of potentially explosive devices sent to British military recruitment centres.
Seven crude devices were mailed to armed forces careers offices in southeast England last week. None went off or caused any injuries.
British government officials said at the time that the devices bore the hallmarks of Northern Irish terror attacks.
Police on Monday said a claim had now been made on behalf of the Irish Republican Army (IRA) paramilitary group.
"The claim was received on Saturday, 15 February by a Northern Irish media outlet using a recognised codeword. The claim was allegedly made on behalf of the 'IRA'," a statement from London's Metropolitan Police said.
The IRA formally ended its armed campaign in 2005, pledging it would use purely peaceful and democratic means towards achieving its goal of a united Ireland.
However, small, dissident splinter groups remain wedded to violence against British state institutions.
Belfast-based newspaper The Irish News reported receiving a statement which said the IRA claims responsibility for the explosive devices that were sent to British armed forces recruitment centres in England.
The statement said attacks would continue when and where the IRA see fit.
The caller used a recognised codeword -- the practice in Northern Ireland when warning of impending terror attacks or claiming responsibility for them, used so the recipient knows it is genuine.
Police urged people to remain vigilant and report anything suspicious.
Dissident republican paramilitary groups reject the peace process in Northern Ireland and continue to carry out attacks, with the intention of destabilising the province and the power-sharing arrangements between the Protestant British and Catholic Irish communities.
