A taxi controller has died more than a week after being assaulted at work, sparking a murder investigation.
The unnamed man, 37, was knocked unconscious at Embassy Cars in Oliver Street in the Nechells area of Birmingham on Friday 26 May, West Midlands Police says.
He was taken to hospital, where he died on Sunday.
Police think a customer went to the firm's office "after being picked up earlier" and there was a disagreement.
The suspect, a male, is said by police to have become aggressive, assaulting the victim.
No arrests have been made, but police say the investigation is "moving at a swift pace".
Det Insp Paul Joyce, from the force's homicide team, said: "We are also liaising with the taxi community to see if they can help supply us with information to identify the suspect."