The deadly shooting is now calling into question the safety and security at airports all across the country.
On Friday, officials at Lambert-St. Louis International say they are focused on preventing a repeat or similar attack.
The airport director tells me it would be impossible of them to prevent everything bad from happening at Lambert, but she said they are constantly assessing possible situations that could pose a threat to passengers and the public.
"When you have a public environment like this, you always have opportunities for something to happen," said Rhonda Hamm-Niebruegge, director of Lambert-St. Louis International Airport.
However, they said their goal is to prevent things as best they can. Every inch of the airport is constantly monitored by a number of law enforcement agencies, from the TSA to the FBI. It's own police force of 70 uniformed and non-uniformed officers also monitor the entire facility.
"We have some of the best K9 units in the country here," Hamm-Niebruegge said.