A man is wanted for arrest in connection with reports of teenagers having their bottoms grabbed in Grimsby and Cleethorpes.
Six similar incidents happened in Cleethorpes Country Park, Bargate, Littlefield Lane, Sheepfold Street and on a cut-through off Westward Ho in the last month.
The latest incident happened on Sheepfold Street, Grimsby, at around 5.30pm on Saturday, March 10.
On each occasion a man has approached his victim from behind, mumbled something and sexually assaulted them before running away, Humberside Police said.
The man then left in the direction of Willingham Street, where he is believed to have got into a car and left the area.
The suspect is described as white, of slim build, between five foot seven and five foot 10 tall and scruffy.
Police would also like to speak to some men who went to the aid of the victim and took her to a safe place.
Chief Superintendent Darren Downs said: “We have conducted a thorough investigation and are following up a number of lines of enquiry.
“As a result of those enquiries we have a suspect who we are actively working to arrest and have increased patrols in key areas – both as a deterrent and provide reassurance.”
Anyone with any information that could assist the police, or if someone has been approached by a man behaving in this way, should contact the police on 101.
Humberside Police have not specified if it is connected to the incident previously reported where a 17-year-old girl was allegedly sexually assaulted by an unknown man on a footpath running from Westward Ho to Littlefield Lane, close to Birkwood Medical Centre, but the description of the man in that case is similar.