Police are looking into a series of cases in which a man approached people with babies and removed their dummies.
Between February 10 and August 7, four occurrences in the Harlow area were reported to Essex Police.
According to the police, a kid was also assaulted on one occasion.
The man has been described as thin and white, in his twenties, with light-brown eyes and yellow teeth.
Police have issued a photograph of a man they want to speak with about the occurrences.
The photograph, which was taken from behind and does not show a face, depicts a man wearing a black hooded top and holding a black Nike bag with a white emblem.
Essex Police are hoping that people recognise the outfit and would like to hear from anyone who recognises the individual or has seen someone matching the description acting suspiciously.
Chief Inspector Paul Austin, District Commander for Harlow, said: “This is a series of unusual incidents and, as a parent myself, I understand the level of concern they will cause.
“However, I want to reassure the people of Harlow that we have detectives dedicated to investigating these incidents, have linked previous incidents, and my teams will be visible out in the community to provided reassurance.
“I would urge you to continue going about your daily business as usual but be vigilant of anyone acting suspiciously.
“I need anyone who has information or recognises this person to contact us.”
Anyone with information, CCTV, dashcam or other footage in relation to these occurrences is asked to call 101 or Crimestoppers anonymously on 0800 555 111.