Fans notice increased security at NFL stadiums across country Sunday

Fans arriving at NFL stadiums Sunday encountered bomb-sniffing dogs, state troopers in parking lots and other measures designed to boost public safety two days after the deadly terrorist attacks in Paris.

Most teams declined to detail in full their security enhancements other than to confirm compliance with the NFL's request to increase law enforcement presence.

The New York Giants asked media members not to take video of security outside gates. But a few of the enhancements were visible to fans and media on the scene, even as NFL senior vice president of security Jeffrey Miller reiterated on ESPN's Outside the Lines that there is "no credible threat that's known to this point to an NFL venue."

At Baltimore's MT&T Bank Stadium, K-9 units were visible outside the stadium, and even inside around the concourse, in a way that regular attendees could not recall having seen before.

In St. Louis, event staff at the Edward Jones Dome wore red shirts and jackets with the word "SECURITY" in large yellow letters. Previously, their shirts had been a less visible shade of yellow with black lettering.

Green Bay, Wisconsin, native Dave Steavpack, who has attended games at Lambeau Field for nearly 30 years, observed a clear uptick in gate security upon arriving Sunday morning.

"They checked everything we had twice before they let us in," Steavpack said. "They're obviously taking no chances."

Meanwhile, hundreds of event staffers at Heinz Field received an out-of-the-ordinary briefing from supervisors before the Pittsburgh Steelers' game against the Cleveland Browns. They were told to be "extra attentive" while checking bags at gates, according to one of the workers, and were provided with a plan to move large numbers of fans to safety if needed.

The Wall Street Journal, citing a stadium security guard and police officer, reported Saturday that one of the terrorist attackers attempted to enter Paris' Stade de France during a soccer game between France and Germany. The attacker had a ticket but was turned away when an explosive vest was discovered. He then detonated the vest while fleeing security, according to the report.

Security officials at all NFL stadiums use hand-held security wands at gates and limit the size and type of bags that can be brought in. This summer, the NFL added full walk-through metal detectors to its list of "best practices" for stadium security, and all 31 stadiums must comply by next year. Some, including Lambeau Field and MetLife Stadium, are using them now at one gate.

Miller said on Sunday morning that the NFL has been operating at a heightened state of alert since the Sept. 11, 2001 terrorist attacks on New York and Washington, D.C. He said the most important part of securing a stadium is noting unusual circumstances in the weeks and months prior to a possible attack.

"Certainly, where terrorists are most vulnerable is their pre-operational surveillance activities, when they're casing the location to try to determine where weaknesses or vulnerabilities lie," Miller said. "So when fans see something on the outer edges that doesn't look right, they should immediately report that to law enforcement."

In East Rutherford, N.J., fans immediately noticed beefed-up security as well as a number of helicopters circulating upon exiting the train outside MetLife Stadium prior to the Giants'game against the Patriots.

"Just the heightened security, there seemed to be more security officers, more AK-47's, more bomb-sniffing dogs,"said Brian Redondo, 32, a Giants season-ticket holder who resides in Brooklyn but also lived in Paris from 2010-2011. "I've never seen them [security officers at the train station] carry AK's before, never seen them toting this much heavy artillery.

"It makes you hyper aware of what happened in Paris."

In Philadelphia, a French flag flew in the parking lot alongside banners for theEaglesand Dolphins prior to their game at Lincoln Financial Field. John Tracey of West Chester, Pennsylvania, was grilling bacon and sausage in the parking lot just north of the Wells Fargo Center, the arena across from Lincoln Financial Field.

Tracey's 18-year-old son, Thomas, spent two weeks in Paris this summer and asked that the French flag be flown today.

The flag was on a pole that usually carries an American flag.

"It seemed appropriate," John Tracey said.

A few hours south, in Landover, Maryland, several Washington Redskins fans noticed more security than normal in parking lots.

Andy Mackintosh of Frederick, Maryland said his father was at Griffith Stadium the day Pearl Harbor was bombed and an announcement came over the loudspeaker, "all servicemen, please report." He also showed up after 9-11 so wasn't deterred now: "Hell, that happened here. But if no one's coming to games now it's because Dan Snyder charges too much for tickets.

Jeff Grizzel, of Falls Church, Virginia, said he "had a brief thought this morning" of skipping the game.

"It is a high-profile place, and there is a lot of people and the possibility is always there," Grizzel said. "But it's not going to stop me. I paused a minute and I thought, 'I'll go and hope for the best.' So it didn't impact my decision."

The feeling was similar in Nashville, Tennessee, prior to the Tennessee Titans' game against the Carolina Panthers. At Mike Petty's tailgate in Lot A on the east side of Nissan Stadium, one friend left a beer bag unattended and security pulled up to check on it, prompting him to keep it closer.

Petty said he and his friends talked about Paris and what could happen in an attack at a stadium like the one they were preparing to enter.

"We still feel like, in the South, in Tennessee, maybe they wouldn't be so foolish as to come over here," Petty said. "It does give you pause when you get a collection of this many people, you never know who would try to do something or make a scene or a statement. It didn't concern me enough to not be here."

NFL Nation reporters Dan Graziano, Jamison Hensley, Rob Demovsky, Nick Wagoner, Phil Sheridan, Jeremy Fowler, Ohm Youngmisuk, John Keim and Paul Kuharsky contributed to this report.