West Midlands Police has praised the public response in assisting officers with their inquiries, after the stabbings in Birmingham on Friday evening.
All cordons have now been lifted from the scene on Union Street.
"We have had a fantastic response from the public so far and their information has proved vital to our investigation."
"Early inquiries suggest that this wasn't random. The attacker appears to have known his victims.
"Our inquiries continue and if there is anyone who saw something on Friday evening and hasn't yet come forward we urge them to call us now on 101."
More top news
Here is your Tuesday morning weather forecast with Helen Plint.
Your Tuesday morning weather forecast with Helen Plint.
Twin boys with a rare genetic condition have defied the odds after becoming the UK's first twin transplant patients.