Faeces was left on a coffee shop chair at a train station after a man was spotted pulling his trousers down and sitting down.
British Transport Police are now appealing for any passengers using, or passing through, Rugby Train Station to come forward with any information.
They have released a CCTV image of the man they would like to speak to in connection with the incident, which happened at 10.45pm on August 28. The faeces was discovered by cleaning staff.
Anyone with information can call BTP on 0800 40 50 40 or text 61016.