The 16-year-old boy was sentenced at Croydon Crown Court on Friday, 16 July to a total of four-and-a-half years in custody and three years on license.
He had previously pleaded guilty on Monday, 12 April to two counts of causing grievous bodily harm, four counts of sexual assault, one count of assault by penetration, and one count of common assault.
A charge of robbery was left to lie on file.
Detective Sergeant Sarah Barrett, who led the investigation, said: “These attacks were random, and completely unprovoked. The actions of this teenager left not only his victims, but the wider community, scared and concerned for their daughters.
“It remains unclear why he carried out these attacks.
“I would again like to take this opportunity to praise the girls who came forward and helped us with our investigation.”
At 8.50am on 4 November 2020, police were called to reports of an injured girl on Moffat Road in Croydon. The 15-year-old girl had been approached by a stranger and stabbed in the leg; she was taken to hospital for treatment and later discharged.
Two days later, at 8.23am on 6 November 2020, police were called to St Paul’s Road in Croydon to reports of an injured girl. Officers and the London Ambulance Service attended. Another 15-year-old girl had been approached by a stranger and stabbed in the arm. She was treated at the scene before being taken to hospital and discharged.
The victims went to separate schools and it is not thought they were known to each other.
Officers from the South Area Command Unit launched an investigation. The offences were linked to four other incidents from November 2019 to October 2020 where teenage girls were approached as they were walking to school and sexually assaulted or assaulted.
The boy was arrested at his residential address in Thornton Heath in the early hours of 8 November 2020.
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