An 11-year-old boy is fighting for his life after being knocked down by a hit-and-run driver.
The youngster was struck by the car in east London on Friday morning, Scotland Yard said.
Police were called to the scene on Bow Road, Tower Hamlets, at 8.13am and the boy was rushed to hospital by London's Air Ambulance.
London Ambulance Service said it treated a boy for a head injury and he was taken to the major trauma centre at an east London hospital in a serious condition.
On Friday evening police said the boy's injuries had become life-threatening and his next of kin were aware.
The driver of the car did not stop at the scene, although the vehicle was found abandoned nearby.
A 25-year-old man who was arrested on suspicion of dangerous driving and failing to stop has been bailed until February.