Police seek witness who tried to trip up stabbing suspect

The moment the knife-wielding man fled as his alleged victim staggered (GETTY IMAGES)

The man pictured trying to trip up a knife attacker as he fled the scene of a stabbing during the Notting Hill Carnival was being sought by police last night, who want to speak to him as a witness.

The middle-aged man, dressed in a grey jumper and denim jeans and holding plastic carrier bags, was photographed sticking out a leg as the attacker made his escape still clutching the blade. A 20-year-old man remained in a stable condition in hospital last night. A 16-year-old from west London has been arrested in connection with the stabbing.

A photographer caught the moment as the knife-wielding man fled while his victim staggered, bleeding heavily, in front of police and a crowd of people, collapsing soon after.