Thames Valley Police is appealing for a specific witness to an exposure incident in Milton Keynes to come forward.
At around 1.45pm yesterday (1/2), a woman tried to enter the baby changing area in Tesco Superstore in McConnell Drive, Wolverton.
She knocked on the door and a man unlocked the door while performing an indecent act.
The woman left the scene without leaving her details.
A 28-year-old man from Milton Keynes was arrested on suspicion of exposure yesterday. He has been released on police bail until 1 May.
Investigating officer PC Robyn Trigg, based at Milton Keynes police station, said: “I am appealing for the woman who witnessed this exposure incident to please come forward.
“She was with a man, who was pushing a child in a pushchair, and a girl at the time.
“The woman, the man she was with, or anyone with information, should call 101 or make a report on our website, quoting reference number 43230048266.
“Alternatively, you can provide information anonymously to the independent charity, Crimestoppers, by calling 0800 555 111 or via its website.”