This is the terrifying moment an autistic teenager had his neck slashed, narrowly missing a major artery, as he was chased through the streets of London.
In CCTV footage the 16-year-old boy sprints away from his attackers as one man cuts the teenager with a weapon.
The teenager was walking alone to a local youth centre in Westminster when he was approached by three men, one of whom asked him what he was looking at it.
The victim instinctively felt scared and quickly ran away from the trio, who pursued him a short distance and attacked him.
The boy was taken to hospital and treated before being released.
"The victim is a vulnerable young person and this was one of only a few times he has walked anywhere alone,” said Acting Detective Chief Inspector Dave Bolton.
“For some unknown reason the three suspects have taken umbrage to him and attacked him with no provocation and no known reason.
“It is sheer luck that the weapon missed his artery and he was not more severely injured,” he added.
The incident happened at 7.20pm on 4 June and police are now looking for three black or Hispanic male suspects. One was wearing a blue Adidas top and another was described as being approximately 16-years-old.
Police are urging anyone with information can call Westminster CID on 07500 766464 or anonymously on Crimestoppers on 0800 555 111.
Video courtesy of The Metropolitan Police