Terror experts are concerned about the security at Sky Harbor International Airport after the attacks in Brussels.
"What makes Sky Harbor vulnerable is the design," NAU Terror expert Dr. James Ness said.
Terrorists always stake out their target, looking for the best time of day for an attack to happen.
"They do dry runs. They go through it. It is planned out to the smallest detail," Ness said.
Sky Harbor officials said that while they haven't made any changes since the attack, they remain at a high level of security and that passengers can get randomly screened anytime and anywhere.
The key is reporting anything unusual.
"Airports are soft targets. So if anything is suspicious, tell law enforcement," Ness said.
Below is Sky Harbor's full statement on security:
“Details of Sky Harbor’s specific security procedures and staffing are security sensitive information. Safety and security are Sky Harbor’s top priorities. There are multiple layers of security at Sky Harbor. Some are obvious to the public and others are not.
While no specific changes have been issued to Phoenix Sky Harbor as a result of the Brussels attacks, our airport remains at a high security level. As always, passengers are subject to random screening anywhere on airport grounds. We employ multiple layers of security throughout our airport system and work closely with the TSA and our law enforcement partners. Travelers are always encouraged to report suspicious behavior to local law enforcement, airport or airline employees.”