Doctors at an east London hospital are to report details of stabbings to help police crackdown on knife crime.
The information will be used by police to target the problem
Staff at Homerton Hospital in Hackney will pass information about the number and location of serious knife attacks during the two-month trial.
This will be used by police to create a targeted response to the problem.
A British Medical Association (BMA) spokesperson said while it supported the initiative, patient confidentiality was still a priority.
The initiative, which is part of the Metropolitan Police's Operation Blunt, follows similar schemes in Scotland.
It is designed to provide police with information and intelligence that can be used to develop appropriate tactics to reduce knife crime in London.
Det Ch Supt Chris McDonald warned that a rise in the amount of recorded of offences was inevitable.
He said: "We have to brace ourselves for that because there is an element of under-reporting.
"There is no question that there'll be greater 'violence against the person' crime statistics than there are at the moment but... let's just get to know what's going on."
If successful the scheme will be rolled out to hospitals across the city.
Dr John Coakley, medical director at the hospital, said it was about sharing information.
"The ambulance has information, the hospital has information and the police have information and it's about bringing all that information together," he said.
A statement from the BMA said: "The BMA supports non-identifiable automatic reporting of gunshot wounds or other violent assaults to the police.
"However patient identity should only be disclosed where this would clearly be in the public interest."