Two women are suspected of working together to steal £500 from a Chorley shopper.
The thieves are believed to have taken the purse from Argos on Market Street, after watching the victim withdraw money from a cash machine inside Lloyds TSB bank.
Police have described the first offender as being of Eastern European appearance, in her late 20s and wearing a black headscarf and coat.
The second woman, who is understood to have acted as a 'look-out' for her accomplice, was wearing a white knitted hat, blue jeans and brown calf-length boots.
CCTV shows that the incident happened at 12.25pm on January 7.
Anyone with information about the bike or purse thefts should call 08451 253545 or Crimestoppers anonymously on 0800 5511.