ProtectUK publication date
If you receive suspicious item call 999 and ask for the police. Clear the area immediately. Do not attempt to open the letter or package. Avoid unnecessary handling. Keep it separate so it is easily identifiable.

How to identify a suspicious package, indicators to suspicious deliveries/mail

General indicators that delivered items may be of concern include:

  • Unexpected items, especially if hand delivered.
  • Poorly or inaccurately addressed, address printed unevenly or unusually.
  • Unfamiliar writing or unusual style.
  • Unusual postmark or no postmark.
  • More stamps than needed for size or weight of package.
  • Marked 'to be opened only by...’or 'Personal' or 'Confidential'.
  • Unexpected or unusual origin (postmark and/or return address).
  • Labelling or excessive sealing that encourages opening at a particular end or in a particular way.
  • Envelope flap stuck down completely (normally gummed envelope flaps leave slight gaps at edges).
  • No return address or return address that cannot be verified.
  • Greasy or oily stains emanating from the package.
  • Odours emanating from the package.
  • Oddly shaped or lopsided.
  • A padded envelope (Jiffy Bag) or other bulky package.
  • Additional inner envelope or other contents that may be difficult to remove.


Person handling package


Explosive or Incendiary Indicators

Rough handling through the postal system means an item received is unlikely to detonate if moved. Any attempt at opening it may set it off or release the contents.

  • Unusually heavy or uneven weight distribution.
  • Small hole(s) in the envelope or wrapping.


Chemical Biological or Radiological (CBR) Indicators 

Additional indicators include:

  • Powders or liquids emanating from the package.
  • Wrapping stained by liquid leakage.
  • Unexpected items or materials found in the package on opening (loose or in a container) such as powdered, crystalline or granular solids; liquids; sticky substances or residues.
  • Unexpected odours observed on opening.
  • Sudden onset of illness or irritation of skin, eyes and nose.


Actions upon discovery of any suspicious delivered item:

  • Avoid unnecessary handling.
  • If you are holding the item, put it down on a cleared flat surface.
  • Keep it separate so it is easily identifiable.
  • Do not move it.


Move away immediately – (Secure the room to prevent unauthorised access)

  • Clear immediate area and each adjacent room, including rooms above and below.
  • If there is any suggestion of chemical, biological or radiological materials, move those directly affected to a safe location close to the incident - keep these individuals separate from those not involved.
  • Prevent others approaching or accessing the cleared areas.
  • Do not use mobile phones or two-way radios in the cleared area or within 15 metres of the suspect package.
  • Communicate regularly with staff, visitors and the public.


Notify police

  • If the item has been opened, or partially opened prior to being deemed suspicious, it is vital that this is communicated to the police.
  • Ensure informants and witnesses remain available to brief the police, and that the accuracy of their observations is preserved.
  • Encourage witnesses to immediately record their observations in writing, and discourage them from discussing the incident or their observations with others prior to the arrival of the police.


Screening mail and courier deliveries: 

  • Possible Indicators that a Delivered Item Might be of Concern please see:  NPSA
  • Action Upon Discovery of any Suspicious Delivered Item NPSA
  • Mail Screening Matters NPSA
Mail handling
Suspicious Item
Threat analysis
Physical Security