Detective Sergeant Derek Shaw, of Alexandra, said police received information to suggest the man in the photo, taken from CCTV footage, could be Mr Bates.
It was taken outside the Alexandra i-SITE Visitor Centre on Centennial Ave, on Monday, February 12 at 8.52am. It shows a man carrying what appears to be a white plastic shopping bag.
The footage does not show the man’s face, which made identification difficult, Det Sgt Shaw said.
"By releasing this image, we hope someone in the community can identify him or provide more information that may be helpful to our investigation."
Det Sgt Shaw said today more than 40 Search and Rescue volunteers from the lower South Island would join a police dog team for a mainly land-based search around Alexandra.
The teams would be searching some areas which were previously difficult to access due to flooding and vegetation.
There had been no official physical search for Mr Bates since the end of last week.
The last confirmed sighting of Mr Bates was 3.50pm on Sunday, February 11, when he was seen at the Z service station on Tarbert St.
Det Sgt Shaw said anyone with information about the CCTV image was urged to contact the police Southern District Command Centre on (03) 471-5002.
