Just relaying a story that happened in the early 90s. We bought a new Chausson Bora about 91 and we were driving up the M1 towards Belfast. Around the Lurgan area I noticed a couple of kids about 12 years old standing on the bridge above the motorway. One of them had what appeared to be a half brick raised above his head. I realised he was about to launch it so I swerved quickly into the outside lane . He was too quick for me and dropped it. It hit the van just above me and bounced off. Luckily there was a piece of checkered plate on the roof to walk on and it only left a small dent. The pair of them jumped onto bicycles and rode off. I was hammering on at the time and dread to think what would have happened if it had come through the front window