Tuesday’s bombings at Brussels show that attackers were able to identify and exploit a vulnerability in a place known for tough security – that while a global push to boost aviation security following the 11 September 2001 attacks in the United States may keep attackers out of planes, it does not keep them out of airports.
“European agencies ask every country to check all passengers and luggage, but nothing between the street and the terminal, and the problem is here,” says aviation consultant Gérard Feldzer, who points out many airports outside Europe screen at airport entrances.
“Others do that, like Beijing and Istanbul for example, but it’s a big investment and difficult to install,” he says.
But some critics say having people line up just to enter an airport creates a new target at the queues, and argue more efficient and less costly measures are available.
“We should be taking a closer look at working with explosive detection dogs, behaviour detection officers who can observe a terminal and see if something isn’t quite right, and I also think there’s a lot to be said for looking at passenger name record data for example,” says Matthew Finn, managing director of aviation security firm Augmentiq, who also says technology could be put to greater use.
“Video surveillance is another area where I believe there’s an opportunity to improve,” he continues. “There’s a lot of pretty good technology out there where you can be doing real-time video content analysis, that will show you or set off an alarm if it sees something it shouldn’t, such as someone hopping over a fence or someone leaving a bag unattended in a public area.”
While Brussels Zaventem airport handles about 23 million passengers per year, the city’s metro sees upwards of 140 million journeys annually, amplifying the security considerations.
“When you have a metro system with multiple stops, multiple entrances at each stop, and a very rapid flow of commuters particularly at peak times, then trafficking and policing that flow of people becomes much more difficult,” says Matthew Henman, head of IHS Jane’s Terrorism and Insurgency Centre in London. He says that, as with an airport, any form of screening at a metro system would shift security concerns elsewhere.
“If you end up with security measures at the entrance to metro systems, you then end up at rush hour times with queues of people, which then become just as attractive of targets for militants, because you have a large gathering of people gathering in single areas.”
As in last November’s attacks in Paris, the Brussels bombings show the Islamic State group is adept at exploiting such vulnerabilities.
“The attackers were aware of the security measures at the airport, they’d obviously done adequate surveillance and reconnaissance of the target to ensure that they’d be able to detonate their devices in a busy area with little security, giving them as much chance of causing maximum casualties as possible,” Henman says.
“The unfortunate possibility that we have to anticipate is that any security measures that we introduce in the wake of these attacks will be evaluated and assessed by the Islamic State, and that they will look for weaknesses and ways to exploit those measures.”