The teenager was arrested in the early hours of Sunday, 8 November at a residential address and is now in custody at a south London police station.
Police were called at 8.23am on Friday, 6 November to St Paul’s Road, Croydon to reports of an injured girl.
Officers and London Ambulance Service attended. At the scene a 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 where her condition was deemed not life-threatening.
This follows an incident at 08:50hrs on Wednesday, 4 November when police were called to reports of an injured girl in Moffat Road, Croydon. At the scene at 15-year-old girl had, again, been approached by a stranger and stabbed in the leg. The victim was taken to hospital where her condition was confirmed as not life-threatening.
The victims both go to separate schools and at this stage it is not thought they are known to each other.
Anyone who witnessed the incidents or has information should call police on 101 or Tweet @MetCC quoting CAD 1294/06NOV.