Police in Calderdale are appealing for information following an incident in Saville Park last week.
The incident occurred in Saville Park Gardens on Wednesday 3 May around 11.40am when a man approached a woman walking her dog and engaged in conversation.
It was reported that the man showed the woman pictures of a dog on his phone before showing the women indecent images of himself.
The woman was not injured during the incident, but it understandably caused considerable distress and concern.
A 56-year-old man has been arrested in connection with the incident and remains in police custody at this time.
Initial enquiries suggest similar incidents have also occurred recently in other parks within Calderdale.
Neighbourhood policing officers are increasing patrols in the areas where incidents have been reported to provide reassurance whilst enquiries are ongoing.
Officers are appealing for anyone with information of incidents that have not yet reported to police to come forward.
Information can be given either using the 101LiveChat function on the website by calling 101 quoting reference 13230245226.