A Sydney university student claims he was sent 'thousands' of messages after he was wrongly identified as the knifeman behind a horrific attack that saw six innocent shoppers killed. Ben Cohen, a 20-year-old first-year computing science student at the University of Technology, was accused of stabbing shoppers at Bondi Junction Westfield on Saturday afternoon. New South Wales Police Minister Yasmin Catley has since identified 40-year-old Queensland man Joel Cauchi as the man who attacked shoppers with a knife.