A 17-year-old boy is said to be in a life-threatening condition after he was stabbed in Grange Road, Bermondsey, late on Saturday night.
Police were called to Grange Road in Bermondsey at 11.15pm on Saturday.
Officers say that a 17-year-old male was found with stab injuries. He was treated at the scene by paramedics before being taken to hospital.
"His condition has been assessed as life-threatening," said a police spokeswoman.
She added: "Three boys – aged 15, 15 and 14 – were arrested on suspicion of grievous bodily harm. They remain in custody at this time. "
Grange Road remained closed between Alscot Road and Dunton Road on Sunday morning.
The police crime scene seemed to centre on the bus stop next to the former Fort pub and the Golden Delight Chinese takeaway, opposite the Bermondsey Health Centre.
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