An apparent terror attack that killed dozens of people Tuesday at the Ataturk International Airport in Istanbul highlights a growing safety concern for airports around the world.
Security experts say airports need to pay more attention to protecting "softer targets" in the most public areas of the airport - including where crowds gather just outside of the security checkpoints.
Video of one explosion at the Istanbul airport shows a huge blast which appears to come from just outside the terminal building. Security experts tell NBC 5 Investigates this kind of attack is hard to defend against, similar to the deadly attack that happened earlier this year in Brussels.
"Soft targets are one of the hardest things to defend against – kind of hence the name 'soft target' – in that there really aren't any layers of security for a soft target. It's a public area," said Jeff Price, aviation security expert and author of Practical Aviation Security.
Istanbul's airport has security checkpoints right at the doors to the terminal, meaning even if the security perimeter is moved outside of the building, terrorists may still find a way to attack it.
"So simply moving the location of checkpoints doesn't solve the problem. You've got to implement other measures to keep those areas secure," said Price.
It's a worry at airports around the world.
In April, NBC 5 Investigates obtained internal records showing Dallas/Fort Worth International Airport police expressed concerns about "insufficient" police staffing in most of the public areas of the airports.
At the time, airport officials said they constantly re-evaluate the situation and have a plan to hire more officers.
"A third of my employees at the airport are in the department of public safety so we are always looking at it. Obviously it's our top priority. And we will continue to look at it," said D/FW CEO Sean Donohue at an April 7 board meeting.
Security experts say having more officers visible at airport entrances is one of the best ways to deter attacks.
"If I was an airport security director at a U.S. airport or any airport right now I would be doing everything I could to deploy additional law enforcement to those areas," said Price.
Tuesday's attack in Istanbul is a reminder that when you get to an airport, to try and get yourself through the security checkpoint as quickly as possible so you are then in an area where people have been screened, security experts suggest.