A teenager has been arrested following reports a motorist drove around Croxley Green ushering women and teenagers to his car before exposing himself.
Hertfordshire Constabulary said two teenage girls were walking in Barton Way at around 6pm on Friday when a man in a black Ford Focus called out to them.
When they approached the man it is reported he indecently exposed himself.
Officers said a short while later, a woman aged in her 30s was walking in Winton Drive when she was spoken to by a man driving a black Ford Focus. When she walked over to talk to him he was indecently exposing himself.
Detective Constable Paul Burton is investigating these incidents and said: "We would like to hear from anyone who remembers seeing a man acting suspiciously or unusually in a black Ford Focus in the area around the stated time of the incident.
"Anyone who saw such a man, or believes they know his identity, or saw anything else unusual or suspicious should contact me immediately via Hertfordshire Constabulary’s non-emergency number 101, citing crime reference C2/14/1207.
"Alternatively call Crimestoppers, the independent charity, anonymously on 0800 555 111."
An 18-year-old man from Watford has been arrested on suspicion of indecent exposure and is currently on bail until July 3.