An air ambulance has been called to Queen Street Retail Park near Preston city centre.
Police sealed off part of the retail park near Aldi and Food Warehouse for the helicopter crew to land.
The incident took place around 5pm on Sunday (7 April).
Police have confirmed a 17-year-old boy was stabbed in Carlisle Street and the air ambulance was called to fly him to Blackpool Victoria Hospital.
A spokeswoman for the North West Air Ambulance told Blog Preston: “We received a call shortly before 5pm and Helimed 75 was dispatched to the incident.
“A patient has been flown to Blackpool Victoria Hospital for treatment.”
Eyewitnesses told Blog Preston they saw a heavy police presence in Queen Street and Avenham Lane.
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