A teenager is in a critical condition after being stabbed.
A 16-year-old boy, from Plaistow, was found on a grass verge of the roundabout at the junction of Limes Avenue and Westmede in Chigwell shortly before 9pm yesterday.
He had suffered a stab wound to his leg.
Police have cordoned off part of the junction and also about 100 houses on the Limes Farm estate in order to conduct door-to-door enquiries.
Witnesses have reported seeing a car leaving the estate between 8.30pm and 9pm.
Police are appealing for the people in the car to come forward and for anyone with information to contact them.