A 33-year-old police constable has died after being punched during a fight outside a Wolverhampton nightclub.
Chris Findley was off duty when he suffered serious head injuries outside Divine Bar, Darlington Street, at about 04:30 GMT on 28 January.
He was walking past the club when he became involved in a row with a man and women leaving the venue, police said.
Fellow officers described PC Findley, who joined West Midlands Police in 2003, as a "selfless and humble man".
The Sandwell-based PC was in a critical condition following the incident and died shortly before 23:00 GMT on Thursday.
West Midlands Police said PC Findley was left unconscious in the road following a "scuffle".
A man and two women were arrested after the incident and bailed until March as inquiries continue.
A post-mortem examination will be carried out in due course to determine the exact cause of PC Findley's death.
'Warm, infectious personality'
Ch Insp Paul Betts said PC Findley, who was single, had spent most of his time with the force working with the neighbourhood police team in Smethwick.
He said: "He is fondly described by his colleagues as a selfless and humble man, always watching out for those in need of cheering up, which he achieved through his warm, infectious personality and sense of humour.
"Chris was a proactive, hard-working officer who was a credit to the service and the communities of Sandwell.
"Chris will be sadly missed by all that knew him and our thoughts and condolences go out to his close friends and family at this difficult time."
Officers said they believed the suspects, who were in their late-teens or early-20s, had been drinking in Divine Bar for several hours. Officers appealed for anyone in the club who saw them to contact the force.
Det Insp Phil Asquith said he wanted to hear from anyone who was driving along Darlington Street at that time of the morning.
He said witnesses may have originally written off the incident as a low-level disorder but it was a "very serious assault".