Two sex assaults carried out within an hour of another, including one on a 12-year-old girl, are being investigated by the police.
Police believe the same man carried out the assaults, which took place at 5pm and 5.45pm on Friday, September 18, and are appealing for help from the public in identifying him.
The first attack, on the schoolgirl, took place in Ravensbury Park.
Police believe the attacker then cycled along the Wandle Trail and attacked a 21-year-old woman as she cycled on the Wandle Way footpath between Chaucer Way and Plough Lane.
He is described as white, in his late 20s to early 30s, thin build with light stubble. He was wearing a dark baseball cap, dark hooded top and dark trousers and riding a bicycle.
Detective Constable Katie King from Merton CID said: "We believe that the suspect has used the Wandle Trail to cycle between these two areas.
"If you have seen any suspicious activity along the Wandle Trail or in Ravensbury Park, have been approached by an unknown man on a bicycle, or think you may have witnessed these assaults please call us."
Anyone with information should contact Merton CID on 020 8649 3069 or call Crimestoppers anonymously on 0800 555 111.
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