Comment by markx2

In 2010 I was coming back to the UK from Japan. Walked through security carrying a 500ml bottle of water. Realised after clearing everything that it was in my bag. Turned round, went back to the security and handed them the bottle, saying it's just water but I knew I could not take it on board. The guy there took the bottle, placed it into a recess in the desk/table, pressed a button and lights happened in the recess. Then he gave me the bottle back "Yes, water" and indicated I could board.

The tech has been around for over 15 years.