CCTV taken on March 18 , 2009 , an hour before she last spoke to parents . Shows man walking on Heworth Place , near rear of Miss Lawrence 's home . He returns the night later with bag and pauses as second man walks past . Police believe footage could 'hold key ' to unlocking six-year-old mystery . Footage broadcast today on a giant screen near to Miss Lawrence 's home . Detectives believe missing 35-year-old university chef was murdered .
CCTV taken on March 18 , 2009 , an hour before she last spoke to parents . Shows man walking on Heworth Place , near rear of Miss Lawrence 's home . He returns one minute later with bag and pauses as second man walks past . Police believe footage could 'hold key ' to unlocking six-year-old mystery . Footage broadcast today on a giant screen near to Miss Lawrence 's home . Detectives believe missing 35-year-old university chef was murdered .