The National Football League stepped up security inside and outside stadiums Sunday as America's most popular sports league responded to a series of attacks across Paris that left at least 129 people dead.
The U.S. Department of Homeland Security informed the National Football League there are no known specific threats, but league commissioner Roger Goodell ordered tighter security at all venues.
The league said security at its games is robust.
Two of the coordinated attacks in Paris occurred outside a stadium where France was playing Germany in a soccer match.
Mandatory metal detector
The NFL, has mandatory metal detector screening at its games and employs "multiple layers of perimeter security external" at stadiums, told fans coming to NFL games on Sunday to expect lineups and delays.
Among the new precautions is a complete ban on entering stadiums with backpacks, satchels or purses. If any essentials are needed, the NFL said fans should carry them in small, clear plastic bags. Inspections by security guards could delay fans from getting to their seats after traditional pre-game "tailgating" barbecues in the parking lot.
About 17 million spectators attend NFL games every year. The league plans to hold a moment of silence before its 12 Sunday games to honor the victims in the Paris attacks.