Detectives are calling for two men who may have witnessed a sexual assault in Chesterfield to come forward.
The incident happened at around 12.45am on Saturday, May 25. A 32-year-old woman was assaulted as she walked through the grounds of the Crooked Spire church.
There were two men in the Church Walk area at the time, using mobile phones. Police believe they may have heard or seen something suspicious and used their phones to try and cast light on the scene.
Officers have been trying to trace the men but they have yet to come forward.
Anyone with information should call police on 101 or Crimestoppers on 0800 555 111.