A black suspect killed one man and wounded seven other people, Sunday, in a two-hour stabbing rampage across Birmingham city centre.
According to West Midlands Police, the first stabbing was in Constitution Hill at 00:30 BST, then the killer moved south.
The attacker went on to stab people in Livery Street, Irving Street and finally in Hurst Street, where the city's Gay Village meets the Chinese Quarter, at about 02:20 BST.
Savvas Sfrantziz, who owns Mykonos bar on Hurst Street, where one of the attacks took place, told Sky News: "I saw him stabbing the girl several times in the neck. I was only about 20 yards away.
"She started screaming: 'He's stabbing me.' But everybody thought he was robbing her because she had a necklace.
"He wasn't concerned, he wasn't worried, after he stabbed the girl he started walking away."
Another eyewitness, Nikita Denton, of Edgbaston, described how she helped another woman who was "on the street bleeding heavily."
"My best friend Jay held her head and talked her through everything the whole time and wouldn't leave her side," Denton said. "She looked very dazed and confused, she couldn't talk. But she was talking to my friend with blinks."
When paramedics arrived at the scene, Denton said, "I got water and used the torch on my phone to help them see the wounds as they didn't have a torch at that time."
A spokesperson for West Midlands Police said: "We can now confirm that we've launched a murder investigation following the events in Birmingham city centre overnight.
"A man has tragically died. Another man and a woman have suffered serious injuries and five others have also been injured, although their injuries are not thought to be life-threatening.
"We believe the incidents, which took place between 12.30am and 2.20am, are linked and we're doing all we can to find whoever was responsible."
West Midlands Police did not reveal exactly at which of the locations the murder took place; but say there were multiple stabbings at each of the locations.
They say detectives continue to hunt for a lone knifeman. They are reviewing CCTV in the area and are appealing for anyone with mobile phone footage to come forward.
Prime Minister Boris Johnson thanked emergency services "working hard at the scene."
"All my thoughts are with those affected by the terrible incident in Birmingham last night," he tweeted.