there is currently a Spam Virus going around to USPS custumers.
It is disquised as a Postage dilivery message saying they have information on a intercepted package and to click on the link below to get the information.
When you click on the link the Virus is unleashed onto your computer and steals all of your personal data and anything that they want, they can have,also on top of stealing your information there is a threatning virus that will trash your computer.

here is the link to the information pertaining to this thread https://postalinspectors.uspis.gov/radDocs/consumer/SpamAlert.pdf