Six sexual assaults against women and a 14-year-old girl are thought to have been carried out by a delivery driver on a moped, the Met Police has said.
Between 3 March and 18 April, six people were assaulted late at night in the Hornsey, Crouch End and Stroud Green areas of Haringey in London.
The force said they were approached by the moped rider, who then followed and sexually assaulted them.
Police believe he could be working as a food delivery driver or courier.
He is described as wearing dark clothing and his moped had a box attached to the back.
Officers have advised the public to be careful when walking alone in the area at night.
Two of the assaults took place on Despard Road, on 16 and 29 March.
Other attacks were reported on Malvern Road, The Broadway, Nelson Road and Lancaster Road.
The victims' ages range from 14 to 29 and all but one of the assaults happened after 22:00.
Det Insp Pete Dyche said: "We are keeping an open mind as to any links amongst these crimes.
"We are carrying out a number of urgent inquiries as part of our investigation and are doing our utmost to catch the perpetrator(s).
"I would advise that anyone walking alone in the evening in these areas to be mindful of their surroundings and to report any suspicious activity to police immediately."