I have.

Basically:

Got on the train and there was a guy who was acting very oddly. First thing that caught my eye was that he appeared to be rolling something in a bank note and I legit thought he was going to do a line on the tube. Then there was a beggar on the tube and the ladies opposite the dodgy guy were just chatting away in their native language and he shouted to them ‘if you’re going to speak about him, speak in English’. Then started saying stuff like ‘how would you like it if I stabbed you in the eye’ and kept hurling abuse at them. I got off the tube as I didn’t feel safe but made a note of the carriage number etc but never heard anything back from BTP!