A man stabbed in Farringdon was given first aid by an unknown woman - and police are asking her to come forward.

The 20-year-old victim suffered an arm injury during the incident in Clerkenwell Road, at the junction with Vine Hill, around 7.30pm on February 22.

Police are trying to trace a woman who assisted the man and is believed to have witnessed the incident, but left the scene before officers could take her details.

She is thought to have described herself as medical professional who works in surgery - possibly at a nearby hospital.

The Met said the victim was taken to hospital for treatment and his condition was not life-threatening.

A 30-year-old man was arrested near the scene on suspicion of GBH and later released on bail.

PC George Child of the Met's Central North command unit covering Camden and Islington said: "We've contacted a number of local hospitals to trace this woman, who we think could have vital information for our investigation.

"I want to reiterate she is treated only as a witness and is not in any trouble.

"I would like her to make contact with us as soon as possible."

Police are asking the woman, or anyone who thinks they know her, to call 101 and provide reference CAD 7038/22 Feb.

Alternatively, tweet @MetCC or anonymously contact Crimestoppers on 0800 555 111.