A 15-year-old boy is fighting for his life after he was stabbed in the street.
Police have launched an investigation following the incident on Uvedale Road, Dagenham, at around 7.30pm on Saturday.
Paramedics and an air ambulance were rushed to the scene and the boy was taken to hospital where his condition is said to be life threatening.
Cops said no arrests have yet been made but called on the public "to do the right thing" and give up information.
A statement from the Metropolitan Police said: "Hard calls save lives. Are you close to someone on the fringes of knife crime?
"Do the right thing, please give information, 100 per cent anonymously, through the independent charity Crimestoppers.
"No piece of information about knife crime is insignificant or too small.
"Any information you give to Crimestoppers can make a difference in reducing knife crime and the harm it causes to families.
"Crimestoppers never ask your name and they cannot trace your call, your IP address or the device you use. Fill in their quick online form or call 0800 555 111. It could save a life."
Detectives from the Met's East Area CID are now conducting enquiries.
Anyone who witnessed the crime or have information that could help police should call 101 ref CAD 6527/27 August.
