Two teenagers are in hospital following a collision between a bus and a moped.
One of teenager had been stabbed and was being rushed to hospital by his friend on the moped when they pulled out into the path of the bus.
One boy has a damaged liver and the second has a compound spine fractured.
A spokesman for the Met Police said :
Officers remain at the scene in St James Road, Croydon, following the incident which police were called to at 12.44am on Monday, 6 January.
The teenage boys were taken to hospital with serious injuries and we await updates on their condition.
There are diversions in place as officers carry out enquiries.
St James Road remains closed at this time, between Windmill Road and Hogarth Crescent. Some bus routes are affected.