This is the shocking moment a man was spotted openly smoking from a "crack pipe" - in a packed Tube carriage.<br /><br />A commuter said he was "in complete disbelief" when he discovered the apparent drug use on a busy Northern line train between Stockwell and London Bridge. <br /><br />The alarming video shows the man, who is wearing a green beanie and is sat in the priority seat of the train, smoking from a pipe. <br /><br />Commuters around him can be seen looking on in confusion while one passenger says a strong chemical smell filled the carriage.
