Israel is known for its stringent airport security, the result of a string of Palestinian attacks on Israeli planes in the 1970s. Routine security procedures start far away from the terminal.

Before even entering the airport, all cars are stopped for a security check by armed guards. Cameras scan license plates to match them with a database of suspicious vehicles. Security officials said it’s one of the many security filters passengers pass before boarding flights, some of them unknown to the passengers and many others still kept secret.

Before approaching the ticket counter, passengers are thoroughly questioned by “selectors” who look for travelers who match a suspicious profile.

“In the U.S., profiling is a bad word,” Nathum Liss, of the Israeli Airports Authority said, but he defended the practice, saying it is done by “intelligent, motivated” university students who served in Israel’s military and can identify passengers who could pose a potential risk.