Watch above: Armed police patrol Plymouth's city centreA martial arts expert is offering free workshops teaching Plymouth people how to survive a knife attack - and defend themselves against deadly terrorists.Anton St James, owner of Masters Academy in Stonehouse, says people need to be prepared to take action if confronted by a vicious attacker.Following the recent incident in London, Mr St James felt he could use his expertise to educate the public."We use self-defence as a martial arts...
