This is not an emergency in any way but I'm not really sure what to do. I had a quick google and that didn't enlighten me. I am therefore turning to people who might!
In short, I was just walking home through the town centre when a man on a bicycle stopped and asked whether I was a student. He then asked whether I knew anyone who wanted to buy a female bicycle with a lock i.e. the one he was riding. Typed out it seems very inoffensive and completely ridiculous to consider reporting it, however I had the very strong impression it was stolen from the appearance of the bicycle to his behaviour and the way he asked. Is this something the police would want to know - I have very little information apart from a description of him and the bicycle.
Thank you in advance for your advice - even if it is to tell me I'm being silly - I just don't want to fail in my "duty to be a good citizen".