Potential new witnesses are being urged to come forward in relation to the alleged serious sexual assault of a deaf woman in Lincoln.
The attack on the 22-year-old, happened behind Sippers pub in Broadgate, on December 18, 2010, between 1.30am and 3am.
In October last year Lincolnshire Police released a picture of the man seen here in the black top. He has still not been identifed.
Now, after reviewing more footage, these images of two potential witnesses have been revealed. They are not suspects but may be able to help police with their enquiries.
Officers are appealing for them, or anyone who knows them to get in touch.
Contact DS Cunningham at Lincolnshire Police with information on 101.Alternatively call Crimestoppers anonymously on 0800 555111.