A man seen fleeing a road where an 86-year-old woman was found dead in her home is being sought by police.
Riasat Bi was found stabbed in Aubrey Road, Small Heath, Birmingham, at about 11:00 BST on Thursday, West Midlands Police said.
The force want to speak to a man who was seen running from the area and into Coventry Road at the same time.
A 20-year-old man arrested on suspicion of murder has been detained in hospital in Stoke-on-Trent.
He will be questioned once discharged, police said. Officers said his injuries are not life-threatening.
Det Insp Harry Harrison said officers believe the other man seen running from the road may have information and appealed for him, or anyone who saw him, to come forward.
From Coventry Road, he ran into Malmesbury Road, along Oldknow Road and into Waverley Road, where he was last seen by the bridge.
The man is described as Asian, around 5ft 10in and of slim build. He was wearing dark clothing and a baseball cap.
An 18-year-old man also injured in the attack remains in a critical but stable condition in hospital, the force added.
The address had been cordoned off to allow forensic experts to examine the scene.