Security expert Will Geddes has explained why departure terminals are always going to be vulnerable to terrorist attack.
This follows an attack on Ataturk airport in Istanbul by three suicide bombers on Tuesday night, which has left at least 41 people dead and more than 230 injured. Officials have said the attackers began their attack shortly before 10pm Istanbul time, shooting inside and outside terminal 2.
The attackers blew themselves up after police began to fire at them. Prime Minister Binali Yildirim has said early signs suggest the attackers were acting on behalf of the Islamic State (aka Isis or Daesh).
Geddes, a security specialist, explained that the attack was carried out in a similar fashion to the bombings at Zaventem airport in Brussels in March.
"The attack took place in the departures area, the same as we saw in Belgium," he told Paul Ross. "It's a weak area where most people turn up to check in for their flights, and before the security and the secure areas in the inner parts of the airport.
"If you look at somewhere like Istanbul and the airport there, they have a slightly better level of security than in Belgium – they have it at the door when people walk in.
"This is always going to be a constant vulnerability [for everyone], and if they want to introduce greater security, it'll have a massive knock-on effect."
Geddes explained why Turkey is particularly vulnerable to terrorist threats.
"It's been a gateway for individuals who want to join Daesh," he explained. "There have been constant attacks this year, a number of suicide attacks.
"They've been fighting ISIS and the Kurdistan Workers' Party (PKK), who they've had problems with for many years.
"It's becoming increasingly problematic there."