Why did Ryanair-Air Malta plane window blow out mid-air and could it happen again?

For nervous flyers, it sounds like the stuff of nightmares; for most, only contemplated in an action movie. But last week, a passenger really was nearly sucked out through a broken aircraft window mid-flight.

Ljubisa Karović was on a Ryanair-Air Malta flight leaving Thessaloniki in Greece when the adjacent window blew out of the Boeing 737-800, pulling his head and shoulders out of the plane. His wife and fellow passengers helped to keep him inside.

How did this happen – and could it recur?