The public are being asked to report to police immediately if they receive a package in a white A4 envelope with address in grey stencil.
It follows the discovery of a suspicious package at a postal sorting office in the Great James Street area of Foyle.
The PSNI has confirmed tonight (Thursday) that the envelope contained a viable device.
She asked that the public be vigilant and report any such packages arriving in the post or anything suspicious.
Read more news:
Become a member...
Have you considered becoming an Independent member, where not only you support local independent businesses, but you help Armagh I champion a wider, more independent, and impartial range of journalism that matters to your local community – from videos and photos to features and events.
Not only do members get the Independent Card, which gives you exclusive access to fantastic discounts from local businesses but you can get an exclusive members-only newsletter packed with the best deals locally, as well as unique first-look content. Not to mention, our competitions, discounts and giveaways will be made exclusively to our members only. Sign up to become a member or find out more here.Become a member