FedEx Corp. (FDX), operator of the world's biggest cargo airline, will pay $8 million to settle allegations the company improperly blamed delayed delivery of packages sent by the federal government on post-9/11 security measures.

The Justice Department said today that FedEx agreed to resolve a whistleblower lawsuit filed in federal court in Washington that accused the company of violating its money-back guarantee for packages it fails to deliver on time.