Painting in a suspicious manner

The London-based watercolourist Liam O'Farrell writes a letter to The Guardian

I was stopped and searched twice near London City airport – for watercolouring! I was not even facing the airport. I was painting the Tate and Lyle sugar factory opposite. They said they saw me on a camera and thought that "no one would want to paint a factory". I explained that LS Lowry did loads. Then they said I could be an anarchist and I was carrying "suspicious paraphernalia" – this being a flask of coffee and an iPod. Oh, and a box of watercolours.

Once they had all my gear out, rummaged through what identity documentation I had and double-checked it on a few radios, they were satisfied I was just "weird" and left me to it. Until the next week, when I went back to finish off the picture and had to go through the same rigmarole all over again.

I have painted in Ukraine, Russia, Vietnam and plenty of other "controlled" states, and have never been questioned about watercolour anarchism.

This is getting ridiculous.