A boy has been stabbed in front of Boxing Day shoppers in a JD Sports in north-east London.
The Met Police were called to the store on Mare Street in Hackney at about 14:35 GMT.
The victim, thought to be 15 years old, was found outside the shop, police said, and was taken to an east London hospital by air ambulance.
It was the second serious attack in Hackney in as many days, following the Christmas Day stabbing of a man.
The victim, in his mid 20s, was taken to hospital after he was injured in Upper Clapton Road. His injuries are not thought to be life-threatening.
No-one has been arrested over the JD Sports stabbing and inquiries continue.