Generally, the guidelines for handling suspicious and possibly contaminated letters and packages from Domestic Delivery Services contractors are the same as for handling United States Postal Service mail. For more information, visit Mail Center Security. Also, visit the below contractors' websites to see if contractors have posted safety and security updates.

Nongovernment commercial links are provided for the user's convenience.

• AirNet Systems, Inc.
• Cavalier Logistics Management, Inc.
• CorTrans Logistics, LLC
• Astar Air Cargo, Inc. (DHL Express)
• Federal Express Corporation
• UPS Supply Chain Solutions
• United Parcel Service