Police are hunting a man who is believed to have committed at least seven offences against women in London.
The Met Police released an image of the man as part of an appeal for witnesses to come forward in relation to a string of indecent exposures in Tower Hamlets, East London.
The force said on each of the occasions a man wearing a mask cycled up behind a woman before either exposing himself or assaulting them.
In the appeal for witnesses, including any potential victims who had not yet come forward, the force said: "Between the dates of 30 August and 29 September police have been made aware of a male committing a number of offences predominantly in the E3 area.
"At this time, officers are aware of seven offences.
"On each occasion the suspect has cycled up behind a woman before either exposing himself or carrying out a sexual assault.
"On four of the occasions the male has also been reported to have masturbated during the incidents."
The man is described as wearing a black zip hoody, grey joggers with a thick black stripe from hip to knee, a chequered baseball cap and possible a bike lock around his neck. His bike is described as black and silver.
Many of the attacks happened late in the evening, with one taking place in the early hours of the morning.
The locations included Bartlett Park, Burdett Road, Navigation Road and Commercial Road.
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