Police believe this man may have been a key witness to a fight in Northampton town centre which left a 61-year-old fatally injured.
It is thought George Wedderburn, of Byfield Road, St James, was injured after intervening in the fight at Abington Square in the early hours of last Sunday.
He died six days later in hospital.
Police have released this image of a man they think may have tried to act as a peacemaker.
Officers would like him or anyone who knows him to contact them on 101.
Daniel Tero, 22, of Burleigh Road, Kingsthorpe Hollow, has been charged with assault.
He is due to appear at Northampton Crown Court on Wednesday September 3.
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A UKIP councillor has been arrested and given a caution after video footage emerged showing a confrontation between him and another man.
It will be dry with variable cloud, although fog patches could be possible later.
Perhaps a few bright spells, but generally rather cloudy with some showery rain possible at times, especially in the afternoon.