Officers from Avon and Somerset Police are appealing for witnesses after a woman was attacked on the forecourt of a service station in Bristol on Tuesday August 16.
They would like to identify and speak to four witnesses who raised concerns about the incident with service station staff.
A woman in her 40s was headbutted by a man she was with at the Tesco Express service station on Henleaze Road at approximately 5.30pm.
A man, also aged in his 40s, was subsequently arrested on suspicion of causing actual bodily harm. He has since been released under investigation while enquiries continue.
They are asking the four customers who informed Tesco staff of the assault, and anyone else who may have information that could help their inquiry, to contact them.
They are asked to call 101 and give the call handler the reference number 5222197079, or complete the online appeals form.
Information can also be given to Crimestoppers anonymously on 0800 555111 or via its anonymous online form.