The IRA has claimed it sent five parcel bombs to Glasgow and London last week.
Police say a media outlet in Northern Ireland received the claim by a recognised code word yesterday.
Last week a parcel was sent to Glasgow University, while three similar packages were left at transport hubs in London.
No one was injured in any of the incidents.
The MPS & @PoliceScotland are aware of the claim of responsibility, allegedly made on behalf of the ‘IRA’, for the devices that were received at three buildings in #London and at the University of #Glasgow on 5 and 6 March.
https://t.co/8o5mYNhBBr pic.twitter.com/akhu6M8EV5— Metropolitan Police (@metpoliceuk) March 12, 2019
The IRA claims five devices were sent - but only four have been accounted for.
Investigators say they're keeping an open mind and are continuing their enquiries.
No arrests have been made so far.
Justice Minister Charlie Flanagan says he's "deeply concerned to learn of the further developments in the investigation".
Minister Flanagan said:
These actions will only strengthen our resolve to double our efforts to build a truly peaceful future for the people of Northern Ireland.
