A group calling itself the IRA claimed responsibility for sending devices to army recruitment centres by contacting a Northern Irish media outlet on Saturday, police have said.
A Metropolitan Police statement read:
We are aware of the claim of responsibility for the devices that were sent to army recruitment centres in England last week.
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'.
The public is urged to remain vigilant and report anything suspicious to the Anti-Terrorist Hotline 0800 789 321.
More top news
He said that he would put himself forward if a fresh contest is held amid growing calls for him to stand down within the party.
Pet owners and cat lovers are being warned to stay on high alert after the so-called Croydon Cat Killer appeared to strike in another city.
Scotland's First Minister said her government will seek 'immediate discussions' with Brussels to "protect Scotland's place in the EU".