Yesterday i opened a letter assuming it was for me. It was from HM Revenue & Customs, addressed to a person i don't know, with my street address, but with an incorrect postcode.

The letter stated that they have seized a parcel containing Tobacco products which was sent to my address. It then went on to say that a number of similar parcels have been despatched whereby the occupiers of the delivery addresses have not been expecting any parcels. I was told that a number of people based abroad (mainly Hong Kong) are collecting random addresses, and shipping parcels over containing tobacco. They are then waiting outside of these properties for the postman to deliver the goods. Customs are now being much more stringent in their checking and intercepting the parcels.

I was told that they will make a note on their file to say that i (the actual occupier) have nothing whatsoever to do with it, and once they've investigated further they'll fill me in.
So keep an eye out for random people loitering near your houses, because you never know. Customs may let one slip through and it could be your address next.