Police investigating a series of stabbings in Birmingham – one of them fatal – say they have had a "strong response" after releasing CCTV footage of a suspect.
The video shows a man wearing a baseball cap and a dark hoodie with white drawstrings, dark trousers and shoes.
West Midlands Police tweeted that detectives are "following up several new lines of enquiry".
A team is working through the night and anyone with information is urged to call a hotline on 0800 056 0944.
Chief Superintendent Steve Graham said witnesses had been interviewed to "ensure we release the best possible video and image of the man we want to speak to".
The force said extra officers had "flooded the city centre", adding that "four scenes have been held throughout the day and forensic experts have examined each area".
Detectives said there was "no suggestion" the attacks were linked to terrorism.
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A 23-year-old man suffered fatal injuries, police said, while a 19-year-old man and a woman, 32, had critical injuries.
Another five people, aged between 23 and 33, were taken to hospital after also being hurt. Two have been discharged so far.
Mr Graham said: "At this stage we believe that the attacks were random and we have no indication of a motive.
"I would urge people to remain vigilant and report any suspicious behaviour to us."
Anyone who recognises the man is advised not to approach him, and to call 999 immediately.
Earlier, police said they believed the stabbings were linked.
A man who witnessed one of the assaults said he saw the attacker stab a woman "several times" in the neck.
Bar owner Savvas Sfrantziz told Sky News: "She staRead More – Source