A further three people have been arrested on suspicion of murdering a man found “slumped” with a stab wound at the side of a busy road.
The injured man was discovered beside Bristol Road in Birmingham on Saturday and taken to hospital where he died at about 18:15 BST.
Three men aged 22, 30 and 40 were arrested at separate addresses in Nottinghamshire on Sunday, police said.
A woman, 28, and a 15-year-old girl were arrested at the scene on Saturday.
They are also suspected of murdering the man who is yet to be formally identified, police say.
He was attacked just before 17:00 BST and found near the junction with Mill Pool Way in the Bournbrook area.
According to the West Midlands force he was “slumped” with a chest wound.
The woman and girl remain in police custody.
The men are being transported to the West Midlands for questioning.
Det Insp Stu Mobberley said detectives had made “rapid progress overnight having worked with colleagues at Nottinghamshire Police to arrest three men” and were actively seeking “at least one other person”.
Bristol Road, which was closed on Saturday for investigations, has re-opened.
Mill Pool Way remains a police scene.