PHOENIX (KSAZ) - Security in Paris remains tight as thousands of soldiers and police officers work to secure tourist attractions, schools, and government buildings.
In the United States, New York City and Washington D.C. are beefing up security. In NYC extra officers have been deployed to the city's biggest landmarks and attractions, the New York Port Authority, and the Holland Tunnel. The extra security comes as the city unveils the new critical response unit.
Professional sports teams in the United States have also announced plans to step up security. In the valley there are several big games happening this week; the Suns, Cardinals, and the Coyotes are all hosting home games along with Arizona State University.
So what are local authorities doing to keep fans safe? The teams aren't talking, but many regulars say they saw a bigger police presence than normal.
"Of course it's on your mind when you see the attack in Paris, or what happened in Beirut, you're always going to have those things on the back of your mind," said one fan.
"Like in Paris, you know that was a big thing, something like that to happen out of the blue, people just coming in and start shooting," said another fan.
Many say you can't let fear interfere with your life, despite new threats from ISIS to strike in the US.
Daniel Rothenburg is the co-director of the Center for the Future of War at ASU. He's extensively studied ISIS and says fear is what these terrorists prey on.
"There's a desire on the part of terrorists to terrorize, and there is some sense accepting that state of terror in a way in which a group like ISIS, that's quite far from us that can achieve victory by convincing people in their daily lives that they're not safe," said Rothenburg.
Valley law enforcement agencies say they were operating normally, others said they don't discuss any changes in operations. Many reiterated the advice, if you see something, say something.