Government Plan for Response to Biological Attack at Super Bowl Left on Plane

The Philadelphia Eagles celebrate after defeating the New England Patriots 41-33 in Super Bowl LII at U.S. Bank Stadium on Feb. 4, 2018, in Minneapolis. Hannah Foslien/Getty Images

A secret Department of Homeland Security (DHS) document detailing the response plans for a simulated biological attack on the Super Bowl was left in the seat pocket of a commercial airplane, CNN reported on Monday.

A CNN employee discovered the document in December along with a boarding pass and a travel schedule of a DHS BioWatch program manager.