Homeland Security insists there is no "specific, credible" threat of an attack at Super Bowl 50 on Sunday.
On Wednesday, Secretary of Homeland Security Jeh Johnson met with local law enforcement officials and the NFL security team to oversee the Department of Homeland Security's operations that will help ensure the safety of employees, players and fans during Super Bowl 50.
And Johnson says there is nothing untoward ahead of the biggest sporting event in the United States, which will see the Denver Broncos go up against the Carolina Panthers at Levi's Stadium in Santa Clara, California.
"At this time, we know of no specific, credible threat against the Super Bowl," Johnson told reporters.
"Dozens of federal agencies and components, including multiple components of the Department of Homeland Security, are contributing to security measures seen and unseen in connection with the Super Bowl."
More than 15 million fans and visitors in and around the San Francisco area will see the "If You See Something, Say Something" message at airports, on bus and rail systems, billboards, magazines and visitor guides.
"The public has a role to play too," Johnson added.
"'If You See Something, Say Something' is more than a slogan. Public vigilance and public awareness contributes to a safe and secure event."
Multiple reports from the Bay Area say security is ubiquitous.
Members of the Department of Homeland Security, the U.S. Coast Guard, the Transportation Security Administration, the Secret Service and FBI, among others, are working with local law enforcement on the ground but also monitoring social media and communication.
According to Yahoo, concrete barriers, helicopters, security cameras, checkpoints and military vehicles can be seen everywhere around Levi's Stadium.
"Every year is different," Johnson said. "The world situation, the threat picture is different every February.
"We learn from the events of the past, but we have to protect against events of the future."