(CNN) -- The National Football League began enforcing enhanced security procedures at Sunday's games "without incident," an NFL spokesman said.
As part of the new procedures, signs were posted outside stadiums alerting fans to the physical inspection they must now undergo to enter.
"Everything went well and entry into the stadiums was normal and without incident," spokesman Greg Aiello told CNN.
The NFL said in announcing the enhanced security that the procedures are something it implemented before the start of the season, not as a result of a stun gun incident at a New Jersey stadium during the league's opening weekend.
Citing safety reasons, Aiello would not go into detail on the latest league-wide security measures, but New York's Buffalo Bills football team sent out a news release last week describing security procedures it planned to enforce at its first home game Sunday.
According to the release, those procedures are in accordance with the NFL's Best Practices policies.
"Specifically, the enhanced portion of the pat-down is for the area from the knees to the ankles," the release stated, further advising that fans arrive early, "especially with the enhanced pat-down now part of the security measures taken."
Fans in Atlanta attending Sunday night's matchup between the Falcons and the Philadelphia Eagles did just that, some arriving as early as two hours before the game.
"I'm all for getting here an extra 30 to 45 minutes ahead of time," one fan told CNN affiliate WSB outside the Georgia Dome.
Fans also arrived early in Charlotte, North Carolina, where the Panthers took on the Green Bay Packers.
"The NFL initiative is to help with fan conduct," Charlie Dayton, director of communications for the Panthers, told CNN affiliate WCNC.
A sign outside Panthers stadium advised attendees that "Security pat-downs are required for admission to today's game. If you refuse a pat-down you will not be admitted into the stadium."
Most fans were in favor of the new security measures Sunday.
"I think it's good," an Atlanta Falcons fan told CNN affiliate WXIA. "I think in order for all NFL fans to be safe, the stepped-up security is a good measure."
Others were wary of the potentially long lines created by the added security.
"It will take forever to get through," Barb Lithander, a Minnesota Vikings fan, told CNN affiliate KARE while waiting to enter the Minneapolis Metrodome. "It seems a bit excessive."
In last week's incident, the stun gun was sneaked past football stadium security at MetLife Stadium in East Rutherford, New Jersey, during a Sunday match-up between the New York Jets and Dallas Cowboys on the 10th anniversary of the September 11 terrorist attacks.
Various fans who were at the game confirmed to CNN that there were more pat-downs and that security was increased outside the stadium.
Despite the procedures, a South Carolina man was able to sneak the cell-phone-sized weapon into the stadium inside his shirt pocket, according to Aiello.
Leroy T. McKelvey, 59, allegedly used the gun on three men in an upper-deck scuffle during Sunday's ballgame, police Sgt. Julian Castellanos said. The men suffered only minor injuries.
McKelvey was charged with three counts of aggravated assault, possession of a stun gun and possession of a weapon for unlawful purposes, according to police.
He was taken to Bergen County Jail and later released on $22,500 bail.
CNN's Rachel Garrett, Chris Boyette, Jordana Ossad and Nina Golgowski contributed to this report.