Police investigating the stabbing of two teenagers in Birmingham's Bullring shopping centre have released a CCTV image of someone they want to speak to.
A 17-year-old boy and an 18-year-old man were found with serious injuries close to the rear entrance of Selfridges, following reports of disorder at the centre on Wednesday.
They were taken to hospital.
West Midlands Police said the attack was believed to be an "isolated incident".
"The two men received nasty injuries in a busy shopping centre, a week before Christmas; there is no place for this level of violence within the city," Det Insp Lauren Glass said.
The 17-year-old suffered a hand injury while the other victim suffered a slash wound to his head and a broken ankle, police said.
The force said an increased police presence in the Bullring would continue during weekend "to offer reassurance to shoppers and visitors to the city".
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