Russell Crowe has helped French police catch a violent thug.The hard man actor spotted a pair of US tourists being mugged as he was leaving a Paris eatery last month. Although the thief escaped, the Hollywood heartthrob got a good look at his face and was able to identify him to police.A source is quoted in Britain's News of the World newspaper as saying: "It happened too fast for him to react but he got a good look at the thug's faceHe comforted the victims until cops came then he went to a police station and identified a mugshot. "The mugger was held then put in a line-up - and Crowe made a positive ID"Earlier this year it was revealed the 'Gladiator' star used to earn a living as a busker. The Oscar-winning actor, who sings with his band 30 Odd Foot of Grunts, has revealed he lived on the poverty line when he had nothing but his guitar to earn a living.He revealed: "There were points in my life when I was busking on the streets for a living"So I know what it's like to live without any material possessions, except for my guitar"